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 A251241 #4 Dec 03 2014 04:06:11 %S A251241 1,2,3,4,5,6,9,11,14,15,19,22,23,29,30,40,43,51,57,61,62,65,79,87,88, %T A251241 94,101,114,124,127,132,137,142,153,158,167,171,175,187,194,204,215, %U A251241 222,233,238,247,269,273,274,277,283,296,301,313,324,329,338,355 %N A251241 Indices of prime powers in A098550. %C A251241 A010055(A098550(a(n))) = 1; for n > 0: A100995(A098550(a(n))) > 0; %C A251241 A098550(a(n)) = A000961(n). %H A251241 Reinhard Zumkeller, <a href="/A251241/b251241.txt">Table of n, a(n) for n = 1..5000</a> %o A251241 (Haskell) %o A251241 a251241 n = a251241_list !! (n-1) %o A251241 a251241_list = filter ((== 1) . a010055 . a098550) [1..] %Y A251241 Cf. A098550, A000961, A010055, A100995, subsequences: A251239 and A251240. %K A251241 nonn %O A251241 1,2 %A A251241 _Reinhard Zumkeller_, Dec 02 2014