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 A155570 #3 Jul 14 2012 11:32:23
%S A155570 0,1,4,9,16,21,25,36,49,61,64,81,84,100,109,121,129,144,169,181,189,
%T A155570 196,201,225,229,241,244,256,289,301,309,324,336,349,361,381,400,409,
%U A155570 421,436,441,469,484,489,516,525,529,541,549,576,601,625,661,669,676,709
%N A155570 Intersection of A003136 and A020669: N = a^2 + 3b^2 = c^2 + 5d^2 for some integers a,b,c,d.
%C A155570 Contains A155710 as a subsequence (obtained by restricting a,b,c,d to be nonzero). Also contains A000290 (squares) as subsequence.
%o A155570 (PARI) isA155570(n,/* use optional 2nd arg to get other analogous sequences */c=[5,3]) = { for(i=1,#c, for(b=0,sqrtint(n\c[i]), issquare(n-c[i]*b^2) & next(2)); return);1}
%o A155570 for( n=0,800, isA155570(n) & print1(n","))
%Y A155570 Cf. A001481, A002479, A003136, A002481, A020668 ff.
%K A155570 easy,nonn
%O A155570 1,3
%A A155570 _M. F. Hasler_, Jan 25 2009