login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Expansion of (Sum_{k>=0} x^(k^4))^16.
1

%I #25 Jun 25 2024 13:10:18

%S 1,16,120,560,1820,4368,8008,11440,12870,11440,8008,4368,1820,560,120,

%T 16,17,240,1680,7280,21840,48048,80080,102960,102960,80080,48048,

%U 21840,7280,1680,240,16,120,1680,10920,43680,120120,240240,360360,411840,360360,240240,120120,43680,10920,1680,120,0

%N Expansion of (Sum_{k>=0} x^(k^4))^16.

%C Number of ways to write n as an ordered sum of 16 fourth powers (A000583).

%H Seiichi Manyama, <a href="/A374014/b374014.txt">Table of n, a(n) for n = 0..20000</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/WaringsProblem.html">Waring's Problem</a>

%F a(A099591(n)) = 0.

%F a(n) > 0 for n > 13792.

%o (PARI) my(N=50, x='x+O('x^N)); Vec(sum(k=0, sqrtnint(N, 4), x^k^4)^16)

%Y Cf. A000583, A002377, A014110, A099591.

%Y Cf. A282288, A374016.

%K nonn

%O 0,2

%A _Seiichi Manyama_, Jun 25 2024