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Number of partitions of n^2 into squares greater than 1.
7

%I #16 Apr 10 2017 12:25:14

%S 1,0,1,1,2,3,5,8,11,28,44,94,167,354,643,1314,2412,4792,8981,17374,

%T 32566,62008,115702,217040,402396,745795,1372266,2517983,4595652,

%U 8354350,15125316,27265107,48972467,87584837,156119631,277152178,490437445,864534950

%N Number of partitions of n^2 into squares greater than 1.

%C a(n) = A078134(A000290(n)).

%H Alois P. Heinz, <a href="/A092362/b092362.txt">Table of n, a(n) for n = 0..500</a>

%F a(n) ~ exp(3*Pi^(1/3) * Zeta(3/2)^(2/3) * n^(2/3) / 2^(4/3)) * Zeta(3/2)^(4/3) / (2^(11/3) * sqrt(3) * Pi^(5/6) * n^(11/3)). - _Vaclav Kotesovec_, Apr 10 2017

%e a(6) = 5: 6^2 = 36 = 16+16+4 = 16+4+4+4+4+4 = 9+9+9+9 = 4+4+4+4+4+4+4+4+4.

%p b:=proc(n, i) option remember; `if`(n=0, 1,

%p `if`(i<2, 0, b(n, i-1) +`if`(i^2>n, 0, b(n-i^2, i))))

%p end:

%p a:= n-> b(n^2, n):

%p seq(a(n), n=0..50); # _Alois P. Heinz_, Apr 15 2013

%t b[n_, i_] := b[n, i] = If[n == 0, 1, If[i<2, 0, b[n, i-1] + If[i^2>n, 0, b[n-i^2, i]]]]; a[n_] := b[n^2, n]; Table[a[n], {n, 0, 50}] (* _Jean-François Alcover_, Nov 11 2015, after _Alois P. Heinz_ *)

%Y Cf. A001156, A037444.

%Y Cf. A093115, A093116.

%K nonn

%O 0,5

%A _Reinhard Zumkeller_, Mar 19 2004

%E Corrected a(0) and more terms from _Alois P. Heinz_, Apr 15 2013