A144905 a(0) = 1; thereafter a(n) = A105749(n)/n.

1, 2, 7, 74, 1596, 58344, 3240840, 254535840, 26862378480, 3667537480320, 629083000385280, 132437508454137600, 33575888768939193600, 10090248381797704243200, 3546915020658948703564800, 1441883923593020355819571200, 671220876625092844683849216000, 354750674999711346878469083136000

Offset: 0

Author

David Applegate and N. J. A. Sloane, Feb 16 2009

Keywords

• nonn

Crossrefs

Cf. A001515, A105749, A144906.

Programs

Maple

B := proc(n, k, M) local i; option remember;
if n = k then 1;
elif k < n then 0;
elif n < 1 then 0;
else
add( binomial(k-1,i)*B(n-1,k-1-i,M),i=0..M-1 );
end if;
end proc;
p:=proc(n,M) add(B(n,k,M),k=0..M*n); end;
l:=proc(n,M) n!*p(n,M); end;
[seq(l(n,2)/n,n=1..30)];