OFFSET
8,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 8..500
FORMULA
E.g.f.: exp(Sum_{j=1..8} x^j/j!) - exp(Sum_{j=1..7} x^j/j!).
MAPLE
G:= proc(n, k) option remember; local j; if k>n then G(n, n)
elif n=0 then 1 elif k<1 then 0 else G(n-k, k);
for j from k-1 to 1 by -1 do %*(n-j)/j +G(n-j, k) od; % fi
end:
a:= n-> G(n, 8)-G(n, 7):
seq(a(n), n=8..30);
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Sep 17 2013
STATUS
approved