A025447 Number of partitions of n into 3 nonnegative cubes.

1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0

Offset: 0

Author

David W. Wilson

Keywords

• nonn

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 0..10000

Programs

PARI

a(n)=sum(a=0,sqrtnint(n,3), sum(b=0,a, my(C=n-a^3-b^3,c); ispower(C,3,&c) && 0 <= c && c <= b)) \\ Charles R Greathouse IV, Jun 26 2013

PARI

a(n)=sum(a=0,sqrtnint(n,3), my(a3=a^3,c); sum(b=0,min(a,sqrtnint(n-a3,3)), ispower(n-a3-b^3,3,&c) && c <= b)) \\ Charles R Greathouse IV, Sep 16 2016