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%I #8 Jun 06 2016 23:21:29
%S 0,0,0,0,0,1,0,0,1,0,0,0,0,1,0,0,0,0,0,0,2,0,0,1,0,0,0,0,1,1,0,0,0,0,
%T 0,1,0,0,0,0,1,0,0,0,1,1,0,0,1,0,0,0,0,2,0,1,0,0,0,0,1,0,0,0,0,0,0,0,
%U 2,1,0,0,0,0,0,0,0,0,0,0,2,0,0,2,0,1,0,0,1,0,0,0,0,1,0,1,0,0,0,0,1,0,0,0,2,0,0,0,1,0,0,0,0,0,0,1,0,0,0,1
%N Number of solutions to the equation x^2+5y^2 = n with x and y > 0.
%H Charles R Greathouse IV, <a href="/A216279/b216279.txt">Table of n, a(n) for n = 1..10000</a>
%o (PARI) a(n)=sum(k=1,sqrtint((n-1)\5), issquare(n-5*k^2)) \\ _Charles R Greathouse IV_, Jun 06 2016
%o (PARI) list(lim)=my(v=vector(lim\1),t); for(y=1,sqrtint((#v-1)\5), t=5*y^2; for(x=1,sqrtint(#v-t), v[x^2+t]++)); v \\ _Charles R Greathouse IV_, Jun 06 2016
%Y Cf. A092573, A119395, A000161, A025426.
%K nonn
%O 1,21
%A _V. Raman_, Sep 03 2012
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