A184258 Number of strings of numbers x(i=1..3) in 0..n with sum i^3*x(i) equal to 27*n.

1, 1, 2, 2, 2, 3, 3, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 17, 18, 20, 22, 23, 25, 27, 30, 32, 34, 37, 39, 41, 44, 46, 48, 51, 54, 57, 60, 63, 66, 69, 72, 75, 78, 82, 86, 89, 93, 97, 100, 104, 108, 113, 117, 121, 126, 130, 134, 139, 143, 147, 152, 157, 162, 167, 172, 177, 182

Offset

1,3

Comments

Row 3 of A184257.

Links

R. H. Hardin, Table of n, a(n) for n = 1..998

Formula

Empirical: a(n) = 2*a(n-1) - a(n-2) + a(n-27) - 2*a(n-28) + a(n-29).

Empirical g.f.: x*(1 - x + x^2 - x^3 + x^5 - x^6 + x^8 + x^18 - x^20 + x^21 - x^23 + x^24 + x^26 - 2*x^27 + x^28) / ((1 - x)^3*(1 + x + x^2)*(1 + x^3 + x^6)*(1 + x^9 + x^18)). - Colin Barker, Apr 12 2018

Example

All solutions for n=5:
..3....0
..3....0
..4....5

Crossrefs

Cf. A184257.

Sequence in context: A334576 A081607 A029060 * A219291 A029160 A285582

Adjacent sequences: A184255 A184256 A184257 * A184259 A184260 A184261

Keyword

nonn

Author

R. H. Hardin, Jan 10 2011

Status

approved