References to sigma
197 seqfan posts
Sun Jun 10 07:56:51 CEST 2012 [seqfan] sigma(n) / d(n)
Sun Apr 15 00:38:28 CEST 2012 [seqfan] Re: A conjeture about 34155
Thu Feb 9 17:38:53 CET 2012 [seqfan] Re: Stumped on sums of perfect numbers
Thu Feb 9 01:39:04 CET 2012 [seqfan] Re: Stumped on sums of perfect numbers
Sun Dec 11 19:14:02 CET 2011 [seqfan] Fwd: A conjecture of yours
Wed Nov 2 15:48:07 CET 2011 [seqfan] Which sequences maximize sigma(a(n))/(a(n) log log a(n) ) ?
Tue Aug 16 20:47:50 CEST 2011 [seqfan] Re: Sigma-related sequence not in OEIS, need 4th term
Tue Aug 16 17:40:05 CEST 2011 [seqfan] Re: Sigma-related sequence not in OEIS, need 4th term
Tue Aug 16 11:41:48 CEST 2011 [seqfan] Re: Sigma-related sequence not in OEIS, need 4th term
Mon Aug 15 21:45:30 CEST 2011 [seqfan] Sigma-related sequence not in OEIS, need 4th term
Sat Jul 9 19:35:26 CEST 2011 [seqfan] Re: gcd(n, sigma_2(n))
Sat Jul 9 19:35:26 CEST 2011 [seqfan] Re: gcd(n, sigma_2(n))
Sat Jul 9 16:18:41 CEST 2011 [seqfan] gcd(n, sigma_2(n))
Sun Jun 19 20:57:08 CEST 2011 [seqfan] Re: number theory question about A000593
Sat Jun 18 22:18:52 CEST 2011 [seqfan] Re: number theory question about A000593
Mon Mar 28 15:37:18 CEST 2011 [seqfan] Re: A122036
Thu Mar 24 16:33:46 CET 2011 [seqfan] Re: sigma(4n+1) mod 4 and partitions
Wed Mar 23 14:27:59 CET 2011 [seqfan] sigma(4n+1) mod 4 and partitions
Mon Mar 21 11:29:18 CET 2011 [seqfan] sigma(8n+1) mod 4 = A001935(n) mod 4 up to 10^5. A001935 Number of partitions with no even part repeated
Fri Feb 25 20:25:16 CET 2011 [seqfan] Re: Empirical relation for A180169: Sigma(A180162(n)), where A180162(n) is the smallest N such that sigma(N) is an nth power, or 0 if no such N can be found
Fri Feb 25 17:25:31 CET 2011 [seqfan] Re: Empirical relation for A180169: Sigma(A180162(n)), where A180162(n) is the smallest N such that sigma(N) is an nth power, or 0 if no such N can be found
Fri Feb 25 16:59:32 CET 2011 [seqfan] Re: Empirical relation for A180169: Sigma(A180162(n)), where A180162(n) is the smallest N such that sigma(N) is an nth power, or 0 if no such N can be found
Fri Feb 25 16:45:07 CET 2011 [seqfan] Empirical relation for A180169: Sigma(A180162(n)), where A180162(n) is the smallest N such that sigma(N) is an nth power, or 0 if no such N can be found
Thu Feb 10 17:23:07 CET 2011 [seqfan] Re: Should this be cited as a link to A000396?
Wed Feb 9 15:40:53 CET 2011 [seqfan] Re: Q on multiplicative functions
Mon Feb 7 15:56:21 CET 2011 [seqfan] Re: Q on multiplicative functions
Mon Feb 7 14:58:34 CET 2011 [seqfan] Q on multiplicative functions
Thu Dec 30 23:20:51 CET 2010 [seqfan] Re: Unlikely Integer Sequences
Thu Dec 30 22:14:18 CET 2010 [seqfan] Re: Unlikely Integer Sequences
Thu Dec 30 08:18:30 CET 2010 [seqfan] Unlikely Integer Sequences
Wed Nov 3 22:15:01 CET 2010 [seqfan] Re: Near-perfect numbers
Mon Nov 1 19:06:41 CET 2010 [seqfan] Near-perfect numbers
Sun Oct 10 08:43:41 CEST 2010 [seqfan] Re: sigma(n) < min(sigma(n-1),sigma(n+1)), n=10*m?
Sat Oct 9 11:56:49 CEST 2010 [seqfan] Re: sigma(n) < min(sigma(n-1),sigma(n+1)), n=10*m?
Sat Oct 9 11:53:01 CEST 2010 [seqfan] sigma(n) < min(sigma(n-1),sigma(n+1)), n=10*m?
Wed Oct 6 08:40:02 CEST 2010 [seqfan] A175874: more terms?
Mon Oct 4 15:03:13 CEST 2010 [seqfan] Re: Record values of sigma(n+1)/sigma(n)
Mon Oct 4 09:14:10 CEST 2010 [seqfan] Re: Record values of sigma(n+1)/sigma(n)
Mon Oct 4 08:59:00 CEST 2010 [seqfan] Record values of sigma(n+1)/sigma(n)
Sun Oct 3 05:18:57 CEST 2010 [seqfan] Are all terms in A077087 odd?
Fri Oct 1 07:43:36 CEST 2010 [seqfan] Re: A067081: All terms odd?
Fri Oct 1 07:16:43 CEST 2010 [seqfan] A067081: All terms odd?
Wed Sep 29 18:33:00 CEST 2010 [seqfan] Re: sequence warnings?
Mon Sep 27 01:30:55 CEST 2010 [seqfan] Sigma(T(n))=T(m)
Sun Sep 26 06:48:14 CEST 2010 [seqfan] Re: n-th number whose sum of divisors is a n-gonal number
Sun Sep 26 05:22:18 CEST 2010 [seqfan] Re: n-th number whose sum of divisors is a n-gonal number
Sun Sep 26 04:07:37 CEST 2010 [seqfan] Re: n-th number whose sum of divisors is a n-gonal number
Sat Sep 25 22:43:13 CEST 2010 [seqfan] n-th number whose sum of divisors is a n-gonal number
Wed Aug 25 16:28:33 CEST 2010 [seqfan] Re: unable to reproduce A152218 (sigma divisibility)
Wed Aug 25 16:28:33 CEST 2010 [seqfan] Re: unable to reproduce A152218 (sigma divisibility)
Wed Aug 25 01:00:33 CEST 2010 [seqfan] Re: A162302 (sigma divisibility) incomplete ?
Wed Aug 25 00:53:30 CEST 2010 [seqfan] Re: unable to reproduce A152218 (sigma divisibility)
Wed Aug 25 00:49:53 CEST 2010 [seqfan] Re: A162302 (sigma divisibility) incomplete ?
Wed Aug 25 00:49:26 CEST 2010 [seqfan] Re: unable to reproduce A152218 (sigma divisibility)
Wed Aug 25 00:49:26 CEST 2010 [seqfan] Re: unable to reproduce A152218 (sigma divisibility)
Wed Aug 25 00:40:19 CEST 2010 [seqfan] unable to reproduce A152218 (sigma divisibility)
Wed Aug 25 00:01:26 CEST 2010 [seqfan] A162302 (sigma divisibility) incomplete ?
Tue Aug 24 11:02:09 CEST 2010 [seqfan] Re: A180268
Mon Aug 23 23:11:02 CEST 2010 [seqfan] Re: A180268
Mon Aug 23 22:23:04 CEST 2010 [seqfan] Re: A180268
Thu Aug 19 18:33:40 CEST 2010 [seqfan] Re: A104149 More terms
Thu Aug 19 18:33:40 CEST 2010 [seqfan] Re: A104149 More terms
Thu Aug 19 17:02:49 CEST 2010 [seqfan] Re: Definition of sigma(n) which are powers, A180162
Thu Aug 19 16:41:56 CEST 2010 [seqfan] Re: A104149 More terms
Thu Aug 19 16:36:32 CEST 2010 [seqfan] Re: A104149 More terms
Thu Aug 19 16:03:00 CEST 2010 [seqfan] A104149 More terms
Wed Aug 18 21:26:06 CEST 2010 [seqfan] Re: Definition of sigma(n) which are powers, A180162
Wed Aug 18 21:34:35 CEST 2010 [seqfan] Re: Definition of sigma(n) which are powers, A180162
Wed Aug 18 20:41:07 CEST 2010 [seqfan] Definition of sigma(n) which are powers, A180162
Wed Aug 18 04:58:00 CEST 2010 [seqfan] Re: not all prime
Wed Aug 18 03:34:41 CEST 2010 [seqfan] Re: not all prime
Tue Aug 17 07:41:46 CEST 2010 [seqfan] Re: Is this right? smallest prime factor of smaller of amicable pair
Mon Aug 16 19:22:36 CEST 2010 [seqfan] Re: Is this right? smallest prime factor of smaller of amicable pair
Mon Aug 16 19:03:49 CEST 2010 [seqfan] Re: Is this right? smallest prime factor of smaller of amicable pair
Mon Aug 16 17:43:10 CEST 2010 [seqfan] Re: Is this right? smallest prime factor of smaller of amicable pair
Mon Aug 16 08:48:46 CEST 2010 [seqfan] Re: Is this right? smallest prime factor of smaller of amicable pair
Mon Aug 16 08:24:32 CEST 2010 [seqfan] Re: Is this right? smallest prime factor of smaller of amicable pair
Mon Aug 16 08:14:17 CEST 2010 [seqfan] Is this right? smallest prime factor of smaller of amicable pair
Sun Aug 15 01:02:59 CEST 2010 [seqfan] Re: « King-walking » integers in a square box
Tue Aug 3 06:35:00 CEST 2010 [seqfan] Re: A083207 On an observation of Frank Buss.
Tue Aug 3 05:19:10 CEST 2010 [seqfan] Re: A083207 On an observation of Frank Buss.
Tue Aug 3 03:50:29 CEST 2010 [seqfan] Re: A083207 On an observation of Frank Buss.
Tue Aug 3 03:19:22 CEST 2010 [seqfan] Re: A083207 On an observation of Frank Buss.
Tue Aug 3 03:16:23 CEST 2010 [seqfan] Re: A083207 On an observation of Frank Buss.
Sun Aug 1 23:21:48 CEST 2010 [seqfan] Re: A083207 On an observation of Frank Buss.
Sun Aug 1 21:29:52 CEST 2010 [seqfan] Re: A083207 On an observation of Frank Buss.
Fri Jul 9 16:48:33 CEST 2010 [seqfan] Re: A083207 On an observation of Frank Buss.
Fri Jul 9 00:42:57 CEST 2010 [seqfan] Re: A083207 On an observation of Frank Buss.
Thu Jul 8 22:10:20 CEST 2010 [seqfan] Re: A083207 On an observation of Frank Buss.
Thu Jul 8 20:58:38 CEST 2010 [seqfan] A083207 On an observation of Frank Buss.
Mon Jun 28 22:19:26 CEST 2010 [seqfan] Re: What defines A133992
Mon Jun 28 21:36:52 CEST 2010 [seqfan] What defines A133992
Fri May 7 12:20:30 CEST 2010 [seqfan] Re: Iterating sigma - 1
Fri May 7 06:15:48 CEST 2010 [seqfan] Re: Iterating sigma - 1
Fri May 7 06:05:24 CEST 2010 [seqfan] Re: Iterating sigma - 1
Fri May 7 05:49:28 CEST 2010 [seqfan] Re: Iterating sigma - 1
Fri May 7 05:45:43 CEST 2010 [seqfan] Re: Iterating sigma - 1
Thu May 6 23:46:51 CEST 2010 [seqfan] Re: Iterating sigma - 1
Thu May 6 22:51:15 CEST 2010 [seqfan] Iterating sigma - 1
Sat Apr 24 16:33:02 CEST 2010 [seqfan] Re: Mathematica's or my err?
Sat Apr 24 16:33:02 CEST 2010 [seqfan] Re: Mathematica's or my err?
Sat Apr 24 15:37:44 CEST 2010 [seqfan] Re: Mathematica's or my err?
Tue Mar 16 06:12:11 CET 2010 [seqfan] Re: GF for A147843?
Mon Mar 15 15:11:00 CET 2010 [seqfan] Re: GF for A147843?
Mon Mar 15 14:54:17 CET 2010 [seqfan] GF for A147843?
Sun Mar 14 13:37:17 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Mon Mar 8 16:34:08 CET 2010 [seqfan] Re: tau(n) vs d(n). Was: Is This Sequence Ever Negative?
Mon Mar 8 16:34:08 CET 2010 [seqfan] Re: tau(n) vs d(n). Was: Is This Sequence Ever Negative?
Sun Mar 7 18:53:33 CET 2010 [seqfan] Re: Is This Sequence Ever Negative?
Sun Mar 7 17:39:55 CET 2010 [seqfan] tau(n) vs d(n). Was: Is This Sequence Ever Negative?
Sun Mar 7 17:39:55 CET 2010 [seqfan] tau(n) vs d(n). Was: Is This Sequence Ever Negative?
Sun Mar 7 17:12:19 CET 2010 [seqfan] Re: Is This Sequence Ever Negative?
Thu Mar 4 11:31:47 CET 2010 [seqfan] divisors <= sqrt(n)
Mon Feb 22 22:02:17 CET 2010 [seqfan] Re: A173279 and A173280
Mon Feb 22 21:12:18 CET 2010 [seqfan] Re: A173279 and A173280
Sat Feb 20 17:10:37 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Sat Feb 20 14:40:11 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Thu Feb 18 15:46:01 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Thu Feb 18 08:45:33 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Thu Feb 18 00:41:45 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Wed Feb 17 23:29:17 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Wed Feb 17 23:29:17 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Wed Feb 17 19:02:07 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Wed Feb 17 18:26:33 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Wed Feb 17 18:26:33 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Wed Feb 17 18:06:29 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Mon Feb 15 20:54:25 CET 2010 [seqfan] Re: Mystery tour with a(n)=sigma(a(n-1))
Mon Feb 15 19:38:31 CET 2010 [seqfan] Mystery tour with a(n)=sigma(a(n-1))
Fri Jan 15 21:59:18 CET 2010 [seqfan] Re: Asymptotic for A074753
Fri Jan 15 21:48:26 CET 2010 [seqfan] Re: Asymptotic for A074753
Fri Jan 15 17:54:55 CET 2010 [seqfan] Re: Asymptotic for A074753
Fri Jan 15 02:29:26 CET 2010 [seqfan] Re: Asymptotic for A074753
Fri Jan 15 02:04:17 CET 2010 [seqfan] Re: Asymptotic for A074753
Wed Jan 13 15:44:15 CET 2010 [seqfan] Re: Asymptotic for A074753
Wed Jan 13 05:23:10 CET 2010 [seqfan] Re: Asymptotic for A074753
Wed Jan 13 03:39:14 CET 2010 [seqfan] Re: Asymptotic for A074753
Tue Jan 12 21:46:17 CET 2010 [seqfan] Re: naive sequence generator
Tue Jan 12 21:35:15 CET 2010 [seqfan] Re: naive sequence generator
Tue Jan 12 21:17:40 CET 2010 [seqfan] Re: naive sequence generator
Tue Jan 12 21:10:30 CET 2010 [seqfan] Re: naive sequence generator
Tue Jan 12 18:29:04 CET 2010 [seqfan] Re: naive sequence generator
Tue Jan 12 18:22:26 CET 2010 [seqfan] Asymptotic for A074753
Tue Jan 12 16:47:18 CET 2010 [seqfan] naive sequence generator
Tue Jan 5 22:08:05 CET 2010 [seqfan] Re: A002961: sigma(n)=sigma(n+1).
Tue Jan 5 22:39:15 CET 2010 [seqfan] Re: A002961: sigma(n)=sigma(n+1).
Tue Jan 5 21:22:48 CET 2010 [seqfan] Re: A002961: sigma(n)=sigma(n+1).
Tue Jan 5 20:02:19 CET 2010 [seqfan] A002961: sigma(n)=sigma(n+1).
Sun Jan 3 10:43:11 CET 2010 [seqfan] Re: Comment on A068982 and The Global Cohen-Lenstra Heuristic
Sat Jan 2 19:29:23 CET 2010 [seqfan] Comment on A068982 and The Global Cohen-Lenstra Heuristic
Sat Nov 21 04:18:59 CET 2009 [seqfan] Re: detective work related to "Floretions"
Sat Aug 29 01:32:15 CEST 2009 [seqfan] Re: A000134
Sat Aug 29 00:33:49 CEST 2009 [seqfan] Re: A000134
Sat Aug 29 00:07:01 CEST 2009 [seqfan] Re: A000134
Mon Jul 6 23:59:40 CEST 2009 [seqfan] Re: Destinies of sums of proper divisors.
Mon Jul 6 21:40:43 CEST 2009 [seqfan] R: Seqfan Digest, Vol 10, Issue 5
Mon Jul 6 17:18:48 CEST 2009 [seqfan] [math-fun] Forwarded mail.... (fwd)
Mon Jul 6 15:25:28 CEST 2009 [seqfan] Re: Destinies of sums of proper divisors.
Mon Jul 6 04:59:52 CEST 2009 [seqfan] Re: Destinies of sums of proper divisors.
Mon Jul 6 03:33:20 CEST 2009 [seqfan] Re: Destinies of sums of proper divisors.
Sat Jul 4 22:12:28 CEST 2009 [seqfan] Re: Destinies of sums of proper divisors.
Fri Jul 3 00:06:53 CEST 2009 [seqfan] Re: PF seqence and A151659
Thu Jul 2 09:32:30 CEST 2009 [seqfan] PF seqence and A151659
Fri Jun 26 22:17:05 CEST 2009 [seqfan] Re: correlation A161918 and A030229
Fri Jun 26 21:26:30 CEST 2009 [seqfan] Re: correlation A161918 and A030229
Tue Jun 23 02:49:53 CEST 2009 [seqfan] Re: A151659
Mon Jun 22 22:38:02 CEST 2009 [seqfan] Re: A151659
Mon Jun 22 21:03:22 CEST 2009 [seqfan] Re: A151659
Mon Jun 22 18:12:25 CEST 2009 [seqfan] Re: A151659
Mon Jun 22 12:48:05 CEST 2009 [seqfan] Re: A151659
Mon Jun 22 09:08:37 CEST 2009 [seqfan] Re: A151659
Mon Jun 22 07:51:43 CEST 2009 [seqfan] Re: A151659
Mon Jun 22 01:18:07 CEST 2009 [seqfan] Re: A151659
Sun Jun 21 23:31:46 CEST 2009 [seqfan] Re: A151659
Sat Jun 20 00:22:27 CEST 2009 [seqfan] Re: Duplicate sigma values
Fri Jun 19 15:05:50 CEST 2009 [seqfan] Re: Duplicate sigma values
Fri Jun 19 15:05:50 CEST 2009 [seqfan] Re: Duplicate sigma values
Fri Jun 19 02:52:05 CEST 2009 [seqfan] Duplicate sigma values
Sun Apr 5 08:18:33 CEST 2009 [seqfan] PF Sequence
Wed Apr 8 20:37:12 CEST 2009 [seqfan] Re: Wrong Formula?
Wed Apr 8 20:21:21 CEST 2009 [seqfan] Wrong Formula?
Fri Mar 13 10:02:55 CET 2009 [seqfan] Re: A conjecture concerning connected rooted strength 1 Eulerian graphs with n nodes
Fri Mar 13 07:29:55 CET 2009 [seqfan] Re: A conjecture concerning connected rooted strength 1 Eulerian graphs with n nodes
Thu Mar 5 06:23:52 CET 2009 [seqfan] n/n-1 Multiply Unitary[ Perfect Number
Mon Feb 23 01:29:13 CET 2009 [seqfan] Re: question on a recursively defined sequence
Mon Feb 23 01:26:44 CET 2009 [seqfan] Re: question on a recursively defined sequence
Mon Feb 2 05:48:11 CET 2009 [seqfan] A144648
Thu Nov 27 17:13:00 CET 2008 [seqfan] Re: Sigma(x)=Sigma(y)=Sigma(z)=Sigma(u)=Sigma(v)=x+y+z+u+v
Thu Nov 27 17:13:00 CET 2008 [seqfan] Re: Sigma(x)=Sigma(y)=Sigma(z)=Sigma(u)=Sigma(v)=x+y+z+u+v
Thu Nov 27 14:37:25 CET 2008 [seqfan] Re: Sigma(x)=Sigma(y)=Sigma(z)=Sigma(u)=Sigma(v)=x+y+z+u+v
Mon Nov 24 23:10:45 CET 2008 [seqfan] Re: Sigma(x)=Sigma(y)=Sigma(z)=Sigma(u)=Sigma(v)=x+y+z+u+v
Sun Nov 23 17:58:35 CET 2008 [seqfan] Re: Sigma(x)=Sigma(y)=Sigma(z)=Sigma(u)=Sigma(v)=x+y+z+u+v
Sun Nov 23 05:27:14 CET 2008 [seqfan] Sigma(x)=Sigma(y)=Sigma(z)=Sigma(u)=Sigma(v)=x+y+z+u+v
Sat Nov 8 23:27:54 CET 2008 [seqfan] Re: Fwd: A nice (decimal) property of 78
Sat Nov 8 21:09:55 CET 2008 [seqfan] Re: Fwd: A nice (decimal) property of 78
Sat Nov 8 19:12:10 CET 2008 [seqfan] Re: Fwd: A nice (decimal) property of 78
Tue Nov 4 21:42:27 CET 2008 [seqfan] Re: Uphi(m)=UPhi(n)=3/4*(m*n)^(1/2)
Tue Nov 4 07:20:21 CET 2008 [seqfan] Uphi(m)=UPhi(n)=3/4*(m*n)^(1/2)
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
sigma
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