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%I #3 Jul 14 2012 11:32:23
%S 0,1,4,9,10,16,25,36,40,49,58,64,73,81,90,97,100,106,121,144,145,160,
%T 169,193,196,202,225,232,241,250,256,265,289,292,298,313,324,337,346,
%U 360,361,388,394,400,409,424,433,441,457,484,490,505,522,529,538,576
%N Intersection of A001481 and A002481: N = a^2 + b^2 = c^2 + 6d^2 for some integers a,b,c,d.
%C Contains A155576 as a subsequence (obtained by restricting a,b,c,d to be nonzero). Also contains A000290 (squares) as subsequence.
%o (PARI) isA155566(n,/* use optional 2nd arg to get other analogous sequences */c=[6,1]) = { for(i=1,#c, for(b=0,sqrtint(n\c[i]), issquare(n-c[i]*b^2) & next(2)); return);1}
%o for( n=1,600, isA155566(n) & print1(n","))
%Y Cf. A001481, A002479, A003136, A002481, A020668 ff.
%K easy,nonn
%O 1,3
%A _M. F. Hasler_, Jan 25 2009
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