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%I #12 Feb 02 2017 19:10:10
%S 0,1,5,16,58,171,434,1030,2259,4645,9071,16927,30354,52586,88351,
%T 144425,230347,359329,549338,824505,1216843,1768278,2533124,3581117,
%U 5000891,6904149,9430598,12753622,17086885,22692075,29887626,39058827,50669397,65274492,83535475
%N Number of sets of exactly ten positive integers <= n having a square element sum.
%H Alois P. Heinz, <a href="/A281870/b281870.txt">Table of n, a(n) for n = 10..1000</a>
%e a(11) = 1: {1,3,4,5,6,7,8,9,10,11}.
%e a(12) = 5: {1,2,3,4,5,7,9,10,11,12}, {1,2,3,4,6,7,8,10,11,12}, {1,2,3,5,6,7,8,9,11,12}, {1,2,4,5,6,7,8,9,10,12}, {1,3,4,5,6,7,8,9,10,11}.
%p b:= proc(n, i, t) option remember;
%p `if`(i<t, 0, `if`(n=0, `if`(t=0, 1, 0),
%p `if`(t<1 or n<t*(t+1)/2 or n>(t+1)*(2*i-t)/2, 0,
%p `if`(i>n, 0, b(n-i, i-1, t-1))+b(n, i-1, t))))
%p end:
%p a:= proc(n) option remember; `if`(n<0, 0, a(n-1)+add(
%p b(j^2-n, n-1, 9), j=isqrt(n-45)..isqrt(10*n-45)))
%p end:
%p seq(a(n), n=10..60);
%Y Column k=10 of A281871.
%K nonn
%O 10,3
%A _Alois P. Heinz_, Feb 01 2017
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