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 A269399 #10 Mar 20 2016 12:54:26 %S A269399 3,5,9,10,12,15,17,26,30,31,33,34,40,41,45,48,49,50,52,61,65,67,68,70, %T A269399 78,80,85,90,91,93,94,96,97,99,101,102,104,105,108,112,113,115,117, %U A269399 123,124,127,133,154,155,158,159,161,162,164,168,173,174,178,179,181,182,188,189,191,193,194,196,197,199,202,204,208,210 %N A269399 Numbers n for which prime(n+7)-prime(n+6) is a multiple of three. %H A269399 Antti Karttunen, <a href="/A269399/b269399.txt">Table of n, a(n) for n = 1..10000</a> %F A269399 a(n) = A270190(n) - 6. %e A269399 3 is present as the difference between A000040(3+7) = 29 and A000040(3+6) = 23 is 6, a multiple of three. %t A269399 Select[Range@ 210, Divisible[Prime[# + 7] - Prime[# + 6], 3] &] (* _Michael De Vlieger_, Mar 18 2016 *) %o A269399 (Scheme, with _Antti Karttunen_'s IntSeq-library) %o A269399 (define A269399 (MATCHING-POS 1 1 (lambda (n) (= 0 (A137264 (+ 6 n)))))) %o A269399 (PARI) isok(n) = ((prime(n+7) - prime(n+6)) % 3) == 0; \\ _Michel Marcus_, Mar 18 2016 %Y A269399 Complement: A269389. %Y A269399 Cf. A137264, A270190. %Y A269399 Cf. also A270199. %K A269399 nonn %O A269399 1,1 %A A269399 _Antti Karttunen_, Mar 16 2016