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%I #4 Jul 14 2012 11:32:23
%S 41,89,164,225,241,281,356,369,401,409,449,521,569,601,641,656,761,
%T 769,801,809,881,900,929,964,1009,1025,1049,1124,1129,1201,1249,1289,
%U 1321,1361,1409,1424,1476,1481,1489,1521,1601,1604,1609,1636,1681,1721,1796
%N Intersection of A000404, A154777 and A154778: N = a^2 + b^2 = c^2 + 2d^2 = e^2 + 5f^2 for some positive integers a,b,c,d,e,f.
%o (PARI) isA155572(n,/* optional 2nd arg allows us to get other sequences */c=[5,2,1]) = { for(i=1,#c, for(b=1,sqrtint((n-1)\c[i]), issquare(n-c[i]*b^2) & next(2)); return);1}
%o for( n=1,1999, isA155572(n) & print1(n","))
%Y Cf. A000404, A154777, A092572, A097268, A154778, A155716, A155717, A155560-A155578.
%K easy,nonn
%O 1,1
%A _M. F. Hasler_, Jan 25 2009
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