OFFSET
20,3
LINKS
Alois P. Heinz, Table of n, a(n) for n = 20..10000
FORMULA
G.f.: (x^15-x^11-x^10-x^8-x^7+x^4+x^3+x^2+1)*x^20 / ((x^2-x+1) *(x^4+x^3+x^2+x+1) *(x^4+1) *(x^6+x^5+x^4+x^3+x^2+x+1) *(x^2+1)^2 *(x^2+x+1)^2 *(x+1)^4 *(x-1)^8).
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Oct 16 2018
STATUS
approved