Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #5 Oct 12 2012 14:40:21
%S 5,31,112,308,714,1470,2772,4884,8151,13013,20020,29848,43316,61404,
%T 85272,116280,156009,206283,269192,347116,442750,559130,699660,868140,
%U 1068795,1306305,1585836,1913072,2294248,2736184,3246320,3832752
%N Seventh column of (1,5)-Pascal triangle A096940.
%C If Y is a 5-subset of an n-set X then, for n>=10, a(n-10) 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.: (5-4*x)/(1-x)^7.
%F a(n)= (n+30)*binomial(n+5, 5)/6 = 5*b(n)-4*b(n-1), with b(n):=A000579(n+6)=binomial(n+6, 6).
%Y Sixth column: A096943; eighth column: A096945.
%K nonn,easy
%O 0,1
%A _Wolfdieter Lang_, Jul 16 2004