OFFSET
0,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..350
FORMULA
a(n) = Sum_{j=0..n} n * (2*n-j)^(n-j-1) * C(n,j) for n>0, a(0) = 1.
MAPLE
a:= n-> `if`(n=0, 1, add(n*(2*n-j)^(n-j-1)*binomial(n, j), j=0..n)):
seq(a(n), n=0..20);
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Dec 21 2014
STATUS
approved