A324358 Total number of occurrences of 8 in the (signed) displacement sets of all permutations of [n+8] divided by 8!.
0, 1, 17, 244, 3455, 50356, 766943, 12274858, 206788751, 3666278080, 68339173319, 1337340802942, 27431518405607, 588814390368244, 13204430589422015, 308877966133175746, 7525275697320564383, 190678032594396773128, 5017985343328106906711, 136977444553573371090790
Offset: 0
Keywords
Links
- Alois P. Heinz, Table of n, a(n) for n = 0..443
- Wikipedia, Permutation
Programs
-
Maple
a:= n-> (k-> -add((-1)^j*binomial(n, j)*(n+k-j)!, j=1..n)/k!)(8): seq(a(n), n=0..23);
Formula
E.g.f.: (1-exp(-x))/(1-x)^9.
a(n) = -1/8! * Sum_{j=1..n} (-1)^j * binomial(n,j) * (n+8-j)!.
a(n) = A306234(n+8,8).