|
|
A152653
|
|
a(n) = (n-1)! * Product_{k=1..n-2} (n-k)!.
|
|
1
|
|
|
1, 1, 4, 72, 6912, 4147200, 17915904000, 632073093120000, 203881496916787200000, 665860658410473652224000000, 24162751572399267891904512000000000, 10609496941616618062463314270617600000000000
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,3
|
|
LINKS
|
|
|
FORMULA
|
G.f.: G(0)/2, where G(k)= 1 + 1/(1 - 1/(1 + 1/((k+2)!-(k+1)!)/x/G(k+1))); (continued fraction). - Sergei N. Gladkovskii, Jun 14 2013
a(n) = Det_{i,j = 1..n} i^(j+1), n >= 1, (alternants). - Wolfdieter Lang, Oct 10 2015
|
|
MATHEMATICA
|
Table[(n-1)!Product[(n-k)!, {k, n-2}], {n, 13}] (* Harvey P. Dale, Jul 26 2011 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
EXTENSIONS
|
a(12) provided by Harvey P. Dale, Jul 26 2011
|
|
STATUS
|
approved
|
|
|
|