This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A270189 #17 Mar 20 2016 12:55:31 %S A270189 1,2,3,4,5,6,7,8,10,12,13,14,17,19,20,22,24,25,26,27,28,29,30,31,33, %T A270189 34,35,38,41,42,43,44,45,48,49,50,52,53,57,59,60,61,62,63,64,65,66,68, %U A270189 69,70,72,75,77,78,79,80,81,82,83,85,87,88,89,90,92,93,94,95,98,101,104,106,109,112,113,115,116,117,120,122,124,125 %N A270189 Numbers n for which (prime(n+1)-prime(n)) is not a multiple of three. %C A270189 See A269364 for the effect of the bias that favors these terms over the terms of A270190. %H A270189 Antti Karttunen, <a href="/A270189/b270189.txt">Table of n, a(n) for n = 1..10000</a> %H A270189 Terence Tao, <a href="https://terrytao.wordpress.com/2016/03/14/biases-between-consecutive-primes/">Biases between consecutive primes</a>, blog entry March 14, 2016 %F A270189 Other identities. For all n >= 1: %F A270189 A269849(a(n)) = n. %t A270189 Select[Range@ 125, Mod[Prime[# + 1] - Prime@ #, 3] != 0 &] (* _Michael De Vlieger_, Mar 17 2016 *) %o A270189 (Scheme, with _Antti Karttunen_'s IntSeq-library) %o A270189 (define A270189 (NONZERO-POS 1 1 A137264)) %o A270189 (PARI) isok(n) = ((prime(n+1) - prime(n)) % 3) != 0; \\ _Michel Marcus_, Mar 17 2016 %Y A270189 Complement: A270190. %Y A270189 Disjoint union of A270191 and A270192. %Y A270189 Positions of 1's and 2's in A137264. %Y A270189 Left inverse: A269849. %Y A270189 Cf. A000040, A001223, A269364, A269389. %K A270189 nonn %O A270189 1,2 %A A270189 _Antti Karttunen_, Mar 16 2016