A034962 and A050207 can't both be correct

Artur grafix at csl.pl
Sat Jan 27 10:58:25 CET 2007


Good is:
{23, 31, 41, 59, 71, 83, 97, 109, 131, 173, 199, 211, 223, 251, 269, 311,
349, 439, 457, 487, 503, 607, 661, 701, 829, 857, 883, 911, 941, 1033,  
1049,
1061, 1151, 1187, 1229, 1249, 1303, 1367, 1381, 1409, 1433, 1493, 1511,  
1553,
1667, 1867, 1931, 1973, 1993, 2011, 2129, 2179, 2251, 2269, 2287, 2357,  
2393,
2417, 2441, 2521, 2549, 2579, 2621, 2677, 2971, 3019, 3041, 3121, 3271,  
3329,
3433, 3467, 3539, 3581, 3607, 3631, 3697, 3851, 3863, 3877, 3889, 3911,  
3929,
3947, 3967, 4153, 4231, 4259, 4289, 4337, 4363, 4451, 4481, 4597, 4679,  
4733,
4759, 4817, 4957, 4987, 4999, 5059, 5153, 5197, 5347, 5501, 5669, 5813,  
5903,
5939, 6073, 6121, 6299, 6323, 6353, 6373, 6397, 6421, 6719, 6733, 6761,  
6823,
6841, 6899, 6917, 6983, 7013, 7027, 7039, 7079}
Mathematica procedure:
a = {}; Do[k = Prime[x] + Prime[x + 1] + Prime[x + 2]; If[PrimeQ[k],  
AppendTo[a, k]], {x, 1, 350}]; a

ARTUR





Dnia 27-01-2007 o 01:22:32 Jonathan Post <jvospost3 at gmail.com> napisał(a):

> Which of these, if either, is right, and which is wrong?
>
> A034962 Primes which are the sum of three consecutive primes.
> 	23, 31, 41, 59, 71, 83, 97, 109, 131, 173, 199, 211, 223, 251, 269,
> 311, 349, 439, 457, 487, 503, 607, 661, 701, 829, 857, 883, 911, 941,
> 1033, 1049, 1061, 1151, 1187, 1229, 1249, 1303, 1367, 1381, 1409,
> 1433, 1493, 1511, 1553, 1667, 1867, 1931, 1973, 1993
>
> A050207 Primes that are the sum of three consecutive primes.  	
> 	23, 29, 41, 47, 59, 97, 131, 137, 223, 283, 311, 317, 367, 389, 457,
> 563, 587, 607, 677, 743, 839, 857, 907, 929, 941, 947, 1031, 1049,
> 1093, 1283, 1303, 1453, 1489, 1847, 1867, 1913, 1931, 1993, 2027,
> 2347, 2381, 2441, 2477, 2579, 2617, 2657, 2729, 2749






Dear Seqfans, Franklin noticed that many sequences of
this type were wrong, and Don Reble and others sent in corrected versions.

But there is one sequence left that I'm not happy about -
could someone please check it?  Here is the current entry:
It may be correct, but I would like a confirmation.
Thanks
Neil

%I A068120
%S A068120 13,223,3331,44449,555557,66666629,777777701,888888883,99999999907,
%T A068120 1010101010101010101039,11111111111111111111111,
%U A068120 12121212121212121212121223,1313131313131313131313131327
%N A068120 Smallest prime beginning with exactly n n's.
%K A068120 base,easy,nonn,new
%O A068120 1,1
%A A068120 Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Feb 21 2002
%E A068120 Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 22 2002
%E A068120 a(7) corrected by Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Mar 24 2002
%E A068120 Corrected by T. D. Noe (noe(AT)sspectra.com), Nov 14 2006

[The correction from Tony Noe was just to eliminate a spurious comma,
I think]





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