# [seqfan] Re: [OEIS] Wrong comments

Richard Mathar mathar at strw.leidenuniv.nl
Sat Jan 24 16:18:52 CET 2009

```bj> From seqfan-bounces at list.seqfan.eu Fri Jan 23 22:54:35 2009
bj> Date: Fri, 23 Jan 2009 13:33:20 -0800
bj> From: =?ISO-8859-1?Q?Beno=EEt_Jubin?= <benoit.jubin at gmail.com>
bj> To: "N. J. A. Sloane" <njas at research.att.com>,
bj>         Sequence Fanatics Discussion list <seqfan at list.seqfan.eu>
bj> Subject: [seqfan]  [OEIS] Wrong comments
bj> ...
bj> The wrong comment "Of course n is odd" appears in A154611, A153381,
bj> A153350, A153329, A153309, A153088.
bj> The wrong comment "Of course n is even" appears in A153170.
bj>
bj> I think the author means "All odd/even numbers appear in this sequence".
bj> ...

These can be cured as follows:

%I A154611
%S A154611 1,3,5,6,7,9,11,12,13,15,16,17,18,19,20,21,23,24,25,26,27,29,30,31,33,
%T A154611 35,36,37,39,41,42,43,45,46,47,48,49,51,53,54,55,56,57,59,60,61,62,63,
%U A154611 64,65,66,67,69,70,71,72,73,75,76,77,78,79,81,83,84,85,86,87,89,90,91
%N A154611 Numbers n such that 7n+3 is not prime.
%C A154611 Contains all odd numbers A005408 and all even numbers of the form 2*A153307(k).
%F A154611 Let p prime number, n=[(p^2+2p-3)/7] mod.(p); or, n=[(p^2+4p-3)/7] mod.(p); or, n=[(p^2+12p-3)/7] mod.(p).
%e A154611 Example: 42=[11^2+2*11-3)/7]mod.(11), 42=20 mod(11); 26=[(5^2+4*5-3)/ 7] mod.(5), 26=6 mod.(5); 18=[(3^2+12*3-3)/7] mod.(3), 18=6 mod.(3)
%Y A154611 Cf. A089033, A045437, A017017
%K A154611 nonn,new
%O A154611 1,2
%A A154611 Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Jan 15 2009
%E A154611 Rephrased comment on parity of n - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 24 2009

%I A153381
%S A153381 1,2,3,4,5,7,8,9,10,11,13,14,15,17,18,19,20,21,22,23,25,26,27,29,30,31,
%T A153381 32,33,35,37,38,39,40,41,43,44,45,46,47,48,49,50,51,53,55,56,57,59,60,
%U A153381 61,62,63,65,66,67,68,69,70,71,73,74,75,76,77,79,80,81,83,85,86,87,88
%N A153381 Numbers n such that 11n+5 is not prime
%C A153381 The odd numbers A005408 are a subset.
%F A153381 Let p=prime; n=(p^2-5)/11 mod.(p); n=(p^2+4p-5)/11 mod.(p); n=(p^2+6p-5)/ 11 mod.(p); n=(p^2+16p-5)/11 mod.(p); n=(p^2+18p-5)/11 mod.(p);
%Y A153381 Cf. A108233
%K A153381 nonn
%O A153381 1,2
%A A153381 Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Dec 25 2008
%E A153381 Rephrased comment on parity of n - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 24 2009

%I A153350
%S A153350 1,2,3,4,5,7,9,10,11,12,13,15,16,17,19,21,22,23,25,27,28,29,30,31,32,33,
%T A153350 34,35,37,39,40,41,42,43,44,45,46,47,49,50,51,52,53,55,56,57,58,59,61,
%U A153350 62,63,64,65,66,67,69,70,71,72,73,74,75,76,77,79,81,82,83,85,87,88,89
%N A153350 Numbers n such that 7n+11 is not prime
%C A153350 The odd numbers A005408 are a subset.
%F A153350 Let p = prime number; n=(p^2-11)/7 mod.(p); n=(p^2+4-11)/7 mod.(p); n=(p^2+10p-11)/ 7 mod.(p)
%F A153350 n=(p^2+4-11)/7 mod.(p); correct: n=(p^2+4p-11)/7 mod.(p); [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Jan 07 2009]
%Y A153350 Cf. A101123
%K A153350 nonn,new
%O A153350 1,2
%A A153350 Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Dec 24 2008
%E A153350 Rephrased comment on parity of n - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 24 2009

%I A153329
%S A153329 1,3,4,5,7,9,10,11,13,15,16,17,18,19,21,22,23,24,25,27,28,29,31,32,33,
%T A153329 34,35,37,39,40,41,43,44,45,46,47,49,51,52,53,55,57,58,59,60,61,63,64,
%U A153329 65,67,68,69,70,71,72,73,74,75,76,77,78,79,81,82,83,85,87,88,89,90,91
%N A153329 Numbers n such that 5n+1 is not prime.
%C A153329 Contains all odd numbers A005408 and even numbers of the form 2*A153275(k).
%F A153329 Let p = prime number, n=(p^2-1)/5 mod.(p); n=(p^2+4p-1)/5 mod.(p); n=(p^2+6p-1)/ 5 mod.(p)
%Y A153329 Cf. A024894
%K A153329 nonn
%O A153329 1,2
%A A153329 Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Dec 23 2008
%E A153329 Rephrased comment on parity of n - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 24 2009

%I A153309
%S A153309 1,3,5,7,8,9,11,13,15,16,17,18,19,21,23,25,27,28,29,30,31,33,35,37,38,
%T A153309 39,40,41,43,44,45,47,48,49,51,53,55,56,57,58,59,61,62,63,65,67,68,69,
%U A153309 71,72,73,75,77,78,79,81,82,83,84,85,86,87,88,89,91,93,95,96,97,98,99
%N A153309 Numbers n such that 3n+1 is not prime
%C A153309 Contains all odd numbers A005408 and even numbers of the form 2*A046954(k).
%F A153309 Let p = prime number, n=(p^2-1)/3 mod.(p)
%Y A153309 Cf. A024892
%Y A153309 Adjacent sequences: A153306 A153307 A153308 this_sequence A153310 A153311 A153312
%K A153309 nonn
%O A153309 1,2
%A A153309 Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Dec 23 2008
%E A153309 Rephrased comment on parity of n - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 24 2009

%I A153088
%S A153088 1,2,3,5,7,8,9,10,11,13,14,15,17,19,20,21,23,24,25,26,27,29,31,32,33,34,
%T A153088 35,37,38,39,41,42,43,44,45,47,49,50,51,52,53,55,56,57,58,59,60,61,62,
%U A153088 63,64,65,66,67,68,69,71,73,74,75,77,79,80,81,83,85,86,87,89,91,92,93
%N A153088 Numbers n such that 5n-1 is not prime
%C A153088 Contains all odd numbers A005408 and even numbers of the form 2*(A153380(k)+1).
%F A153088 Let p=prime number, n=(p^2+1)/5 mod.(p); or, n=(p^2+2p+1)/5 mod.(p); or, n=(p^2+8p+1/5 mod.(p)
%Y A153088 Cf. A153355
%K A153088 nonn,new
%O A153088 1,2
%A A153088 Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Jan 03 2009
%E A153088 First 29 replaced by 20, 4 replaced by 44, extended by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 05 2009. Comment corrected, Jan 24 2009

%I A153170
%S A153170 2,4,6,8,10,11,12,14,16,18,20,21,22,24,25,26,28,30,31,32,34,36,38,39,40,
%T A153170 41,42,44,46,47,48,50,51,52,53,54,56,58,60,61,62,64,66,67,68,69,70,71,
%U A153170 72,73,74,76,78,80,81,82,84,86,88,90,91,92,94,95,96,98,99,100,101,102
%N A153170 Numbers n such that 3n+2 is not prime
%C A153170 Contains all strictly positive even numbers of A005843 and the odd numbers of the form 2*A059324(k)+1.
%F A153170 Let p prime number n=[(p^2+2p-2)/3] mod.(2p); (For columns of sound odd place) n=[(p^2+4p-2)/3] mod.(2p); (For columns of sound even place)
%e A153170 *; *, *; *, 11, *; *, *, *, *; *, *, 25, *, *; *, 21, *, *, 47, *; *, *, *, *, *, *, *; *, *, 39, *, *, 73, *, *; *. 31, *, *, 69, *, *, 107, *;
%Y A153170 Cf. A024893
%K A153170 nonn
%O A153170 1,1
%A A153170 Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Dec 20 2008
%E A153170 Rephrased comment on parity of n, changed 2nd 30 to 40. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 24 2009

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