A095670 Eighth column (m=7) of (1,4)-Pascal triangle A095666.

4, 29, 120, 372, 960, 2178, 4488, 8580, 15444, 26455, 43472, 68952, 106080, 158916, 232560, 333336, 468996, 648945, 884488, 1189100, 1578720, 2072070, 2691000, 3460860, 4410900, 5574699, 6990624, 8702320, 10759232, 13217160, 16138848

Offset: 0

Author

Wolfdieter Lang, Jun 11 2004

Keywords

• nonn
• easy

Comments

If Y is a 4-subset of an n-set X then, for n>=10, a(n-10) is the number of 7-subsets of X having at most one element in common with Y. - Milan Janjic, Dec 08 2007

Formula

G.f.: (4-3*x)/(1-x)^8.

a(n) = 4*b(n)-3*b(n-1) =(n+28)*binomial(n+6, 6)/7, with b(n):=binomial(n+7, 7)= A000580(n+7, 7).