OFFSET
0,1
FORMULA
a(n)= (n+9)*(n+6)*(n+2)*(n+1)*(n^2+15*n+20)/144,
G.f.: (15-24*x^2+18*x^3-4*x^4)/(1-x)^7.
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, Dec 23 2003
STATUS
approved