OFFSET
0,10
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..200
EXAMPLE
a(8) = 1: 12345678.
a(9) = 8: 123456798, 123456897, 123457896, 123467895, 123567894, 124567893, 134567892, 234567891.
MAPLE
b:= proc(u, o, t) option remember; `if`(u+o=0, 1, add(`if`(t=7,
b(o-j, u+j-1, 1), b(u+j-1, o-j, t+1)), j=1..o))
end:
a:= n-> b(0, n, 0):
seq(a(n), n=0..35);
CROSSREFS
KEYWORD
nonn,eigen
AUTHOR
Alois P. Heinz, Oct 02 2013
STATUS
approved