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 A000548 #25 Jun 20 2018 01:34:15 %S A000548 1,4,9,16,36,49,64,81,121,144,196,256,324,361,441,484,529,576,729,784, %T A000548 961,1024,1089,1296,1444,1764,1849,1936,2116,2209,2304,2401,2916,3136, %U A000548 3249,3481,3844,3969,4096,4356,4489 %N A000548 Squares that are not the sum of 2 nonzero squares. %C A000548 Squares of nonhypotenuse numbers A004144(n). - _Lekraj Beedassy_, Jul 06 2004 %C A000548 A143574(a(n)) = a(n); intersection of A000290 and A143575. - _Reinhard Zumkeller_, Aug 24 2008 %H A000548 R. Zumkeller, <a href="/A000548/b000548.txt">Table of n, a(n) for n = 1..1000</a> %H A000548 <a href="/index/Su#ssq">Index entries for sequences related to sums of squares</a> %F A000548 A000290 \ A134422. - _R. J. Mathar_, Feb 06 2011 %t A000548 okQ[n_] := n == 1 || AllTrue[FactorInteger[n][[All, 1]], Mod[#, 4] != 1& ]; A000548 = Select[Range[100], okQ]^2 (* _Jean-François Alcover_, Feb 09 2016 *) %K A000548 nonn %O A000548 1,2 %A A000548 _N. J. A. Sloane_ and _J. H. Conway_