OFFSET
0,4
COMMENTS
Triangle is related to the tangent numbers A000182.
REFERENCES
S. Mukai, An Introduction to Invariants and Moduli, Cambridge, 2003; see p. 446.
FORMULA
EXAMPLE
Triangle begins:
1;
0, 1;
2, 0, 2;
0, 8, 0, 6;
16, 0, 40, 0, 24;
0, 136, 0, 240, 0, 120;
272, 0, 1232, 0, 1680, 0, 720;
0, 3968, 0, 12096, 0, 13440, 0, 5040;
7936, 0, 56320, 0, 129024, 0, 120960, 0, 40320;
0, 176896, 0, 814080, 0, 1491840, 0, 1209600, 0, 362880;
353792, 0, 3610112, 0, 12207360, 0, 18627840, 0, 13305660, 0, 3628800;
...
MAPLE
T:=proc(n, k) if k=-1 then 0 elif n=1 and k=1 then 1 elif k>n then 0 else (k-1)*T(n-1, k-1)+(k+1)*T(n-1, k+1) fi end: for n from 1 to 11 do seq(T(n, k), k=1..n) od; # yields sequence in triangular form [Produces triangle with a different offset] # Emeric Deutsch, Jun 13 2005
CROSSREFS
KEYWORD
AUTHOR
N. J. A. Sloane, Jun 10 2005
EXTENSIONS
More terms from Emeric Deutsch, Jun 13 2005
Additional comments from Philippe Deléham, Sep 17 2005
Edited by N. J. A. Sloane, Aug 23 2008 at the suggestion of R. J. Mathar
STATUS
approved