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 A277026 #4 Oct 04 2016 13:31:12 %S A277026 7,8,11,13,16,19,22,25,27,29,32,38,43,46,47,49,50,53,59,61,62,64,65, %T A277026 67,73,75,76,77,79,82,83,85,86,87,89,92,94,97,100,101,103,104,106,109, %U A277026 113,115,116,119,122,124,125,127,128,130,133,134,137,140,141,143,145,146,148,151,152,154,155,163,164,167,168,169,170,173,174,176,178,179,181,184,185 %N A277026 n for which A277023(4n) is not a square, thus A277024(4n) is nonzero. %o A277026 (Scheme, with _Antti Karttunen_'s IntSeq-library) %o A277026 (define A277026 (NONZERO-POS 1 1 (lambda (n) (A277024 (* 4 n))))) %Y A277026 Complement: A277025. %Y A277026 Cf. A277024. %K A277026 nonn %O A277026 1,1 %A A277026 _Antti Karttunen_, Oct 03 2016