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Number of ways in which n can be partitioned as a sum of a square and cube.
8

%I #23 Aug 02 2018 09:33:31

%S 1,2,1,0,1,1,0,0,1,2,1,0,1,0,0,0,1,2,0,0,0,0,0,0,1,1,1,1,1,0,0,1,0,1,

%T 0,0,2,1,0,0,0,0,0,1,1,0,0,0,0,1,1,0,1,0,0,0,0,1,0,0,0,0,0,1,2,2,0,0,

%U 1,0,0,0,1,1,0,0,1,0,0,0,1,1,1,0,0,0,0,0,0,2,0,1,0,0,0,0,0,0,0,0,2

%N Number of ways in which n can be partitioned as a sum of a square and cube.

%C a(A022550(n))=0; a(A179509(n))=1; a(A022549(n))>0; a(A060861(n))=n. [From _Reinhard Zumkeller_, Jul 17 2010]

%H T. D. Noe, <a href="/A045634/b045634.txt">Table of n, a(n) for n = 0..10000</a>

%e a(9)=2 because 9=2^3+1^2 and 9=3^2+0^3.

%p M:=100; M2:=M^2; t0:=array(0..M2);

%p for i from 0 to M2 do t0[i]:=0; od:

%p for a from 0 to M do for b from 0 to M do

%p i:=a^2+b^3; if i <= M2 then t0[i]:=t0[i]+1; fi; od: od:

%p [seq(t0[i],i=0..M2)];

%t max = 100; Clear[a]; a[_] = 0;

%t Do[n = i^2 + j^3; a[n] += 1, {i, 0, Sqrt[max]}, {j, 0, max^(1/3)}];

%t Table[a[n], {n, 0, max}] (* _Jean-François Alcover_, Aug 02 2018 *)

%Y Cf. A022549, A060861, A135910, A135911, A135912.

%K nonn

%O 0,2

%A _Felice Russo_

%E More terms from _Erich Friedman_