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%I #22 May 04 2021 08:49:25
%S 1,3,6,11,18,26,37,50,63,80,96,115,136,159,186,210,239,268,301,336,
%T 368,407,444,487,526,574,619,664,717,764,820,875,930,989,1047,1112,
%U 1175,1238,1307,1375,1444,1521,1592,1669,1745,1828,1907,1988,2073,2161,2252
%N Number of nonnegative solutions to x^3 + y^3 <= n^3.
%F a(n) = [x^(n^3)] (1/(1 - x))*(Sum_{k>=0} x^(k^3))^2. - _Ilya Gutkovskiy_, Apr 20 2018
%o (Python)
%o for a in range(99):
%o n = a*a*a
%o k = 0
%o for x in range(99):
%o s = x*x*x
%o if s>n: break
%o for y in range(99):
%o sy = s + y*y*y
%o if sy>n: break
%o k+=1
%o print(str(k), end=',')
%o (PARI) a(n) = n++; p = Pol((1/(1 - x))*sum(k=0, n, x^(k^3))^2 + O(x^(n^3))); polcoeff(p, (n-1)^3); \\ _Michel Marcus_, Apr 21 2018
%K nonn
%O 0,2
%A _Alex Ratushnyak_, Apr 01 2013
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