OFFSET
0,5
COMMENTS
Number of partitions of n into parts 1, 4, 7 and 9. - Ilya Gutkovskiy, May 18 2017
LINKS
Iain Fox, Table of n, a(n) for n = 0..10000
Index entries for linear recurrences with constant coefficients, signature (1,0,0,1,-1,0,1,-1,1,-1,-1,1,-1,1,0,-1,1,0,0,1,-1).
FORMULA
From Iain Fox, Nov 30 2017: (Start)
a(n) = a(n-1) + a(n-4) - a(n-5) + a(n-7) - a(n-8) + a(n-9) - a(n-10) - a(n-11) + a(n-12) - a(n-13) + a(n-14) - a(n-16) + a(n-17) + a(n-20) - a(n-21), n > 20.
Lim_{n->infinity} a(n)/a(n+1) = 1.
(End)
a(n) ~ n^3/1512. - Vaclav Kotesovec, Dec 22 2017
MATHEMATICA
CoefficientList[Series[1/((1-x)(1-x^4)(1-x^7)(1-x^9)), {x, 0, 60}], x] (* Harvey P. Dale, Aug 19 2014 *)
PROG
(PARI) first(n) = Vec(1/((1-x)*(1-x^4)*(1-x^7)*(1-x^9)) + O(x^n)) \\ Iain Fox, Nov 30 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved