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 A273324 #16 Nov 27 2016 22:05:43
%S A273324 2,5,6,10,11,14,18,21,22,26,27,30,34,37,38,42,43,46,50,53,54,58,59,62,
%T A273324 66,69,70,74,75,78,82,85,86,90,91,94,98,101,102,106,107,110,114,117,
%U A273324 118,122,123,126,130,133,134,138,139,142,146,149,150,154,155,158,162,165,166,170
%N A273324 Integers n such that n^2 + 3 is the sum of 4 but no fewer nonzero squares.
%C A273324 If n^2 + k is a term of A004215, then the minimum positive value of k is 3, obviously.
%C A273324 See also the first differences (A278536) of this sequence.
%H A273324 Antti Karttunen, <a href="/A273324/b273324.txt">Table of n, a(n) for n = 1..10001</a>
%F A273324 a(n) = A000196(1+A278491(n)). - _Antti Karttunen_, Nov 26 2016
%e A273324 2 is in the sequence because 2^2 + 3 = 7 is a term of A004215.
%o A273324 (PARI) isA004215(n) = {n\4^valuation(n, 4)%8==7}
%o A273324 lista(nn) = for(n=1, nn, if(isA004215(n^2+3), print1(n, ", ")));
%Y A273324 Cf. A000196, A004215, A117950, A278491, A278536.
%K A273324 nonn,easy
%O A273324 1,1
%A A273324 _Altug Alkan_, May 20 2016