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 A097271 #8 Feb 16 2025 08:32:54
%S A097271 1,4,6,14,22,30,38,42,46,54,62,66,70,78,86,94,102,110,114,118,126,134,
%T A097271 138,142,150,154,158,166,174,182,186,190,198,206,210,214,222,230,238,
%U A097271 246,254,258,262,266,270,278,282,286,294,302,310,318,322,326,330,334
%N A097271 Numbers that are neither the sum of two nonzero squares nor the difference of two nonzero squares.
%C A097271 Complement of union of A000404 (sum of squares) and A024352 (difference of squares).
%C A097271 Differs from A062316 only in having an initial 1,4.
%H A097271 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SumofSquaresFunction.html">Sum of Squares Function.</a>
%t A097271 Module[{nn=70,sq},sq=Flatten[{Total[#],Abs[#[[1]]-#[[2]]]}&/@Tuples[ Range[ 3nn]^2,2]]//Union;Take[Complement[Range[Max[sq]],sq],nn]] (* _Harvey P. Dale_, Nov 04 2016 *)
%Y A097271 Cf. A000404, A024352, A097268-A097270.
%K A097271 nonn
%O A097271 1,2
%A A097271 _Ray Chandler_, Aug 19 2004