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 A277025 #8 Oct 04 2016 13:31:05 %S A277025 0,1,2,3,4,5,6,9,10,12,14,15,17,18,20,21,23,24,26,28,30,31,33,34,35, %T A277025 36,37,39,40,41,42,44,45,48,51,52,54,55,56,57,58,60,63,66,68,69,70,71, %U A277025 72,74,78,80,81,84,88,90,91,93,95,96,98,99,102,105,107,108,110,111,112,114,117,118,120,121,123,126,129,131 %N A277025 n for which A277023(4n) is square, thus A277024(4n) is zero. %C A277025 Indexing starts from zero because a(0)=0 is a special case in this sequence. %H A277025 Antti Karttunen, <a href="/A277025/b277025.txt">Table of n, a(n) for n = 0..120</a> %o A277025 (Scheme, with _Antti Karttunen_'s IntSeq-library) %o A277025 (define A277025 (ZERO-POS 0 0 (lambda (n) (A277024 (* 4 n))))) %Y A277025 Complement: A277026. %Y A277025 Cf. A002828, A277015, A277016, A277024. %K A277025 nonn %O A277025 0,3 %A A277025 _Antti Karttunen_, Oct 03 2016