A095669 - OEIS

%I #5 Oct 12 2012 14:40:20

%S 4,25,91,252,588,1218,2310,4092,6864,11011,17017,25480,37128,52836,

%T 73644,100776,135660,179949,235543,304612,389620,493350,618930,769860,

%U 950040,1163799,1415925,1711696,2056912,2457928,2921688,3455760,4068372

%N Seventh column (m=6) of (1,4)-Pascal triangle A095666.

%C If Y is a 4-subset of an n-set X then, for n>=9, a(n-9) is the number of 6-subsets of X having at most one element in common with Y. - _Milan Janjic_, Dec 08 2007

%F G.f.: (4-3*x)/(1-x)^7.

%F a(n) = 4*b(n)-3*b(n-1) = (n+24)*binomial(n+5, 5)/6, with b(n):=binomial(n+6, 6)= A000579(n+6, 6).

%K nonn,easy

%O 0,1

%A _Wolfdieter Lang_, Jun 11 2004