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A177939
Array t(n,m)=(n*m)!/(n + m - 1)! read by antidiagonals.
1
1, 1, 1, 1, 4, 1, 1, 30, 30, 1, 1, 336, 3024, 336, 1, 1, 5040, 665280, 665280, 5040, 1, 1, 95040, 259459200, 4151347200, 259459200, 95040, 1, 1, 2162160, 158789030400, 60339831552000, 60339831552000, 158789030400, 2162160, 1, 1, 57657600
OFFSET
1,5
COMMENTS
Antidiagonal sums are 1, 2, 6, 62, 3698, 1340642, 4670455682, 120997245489122,
46164597191147635202, 146361193109155192147499522,....
EXAMPLE
The array starts in row n=1 as:
1,1,1,1,1,...
1,4,30,336,5040,...
1,30,3024,665280,259459200,...
1,336,665280,4151347200,60339831552000,..
1,5040,259459200,60339831552000,42744736671436800000,..
MAPLE
A177939 := proc(n, m)
(n*m)!/(n+m-1)! ;
end proc: # R. J. Mathar, Jul 14 2012
MATHEMATICA
Clear[t, n]
t[n_, m_] = (n*m)!/(n + m - 1)!;
a = Table[Table[t[n, m], {m, 1, 10}], {n, 1, 10}];
Table[Table[a[[m, n - m + 1]], {m, 1, n}], {n, 1, 10}];
Flatten[%]
CROSSREFS
Sequence in context: A078536 A173918 A174412 * A209196 A158390 A228836
KEYWORD
nonn,tabl
AUTHOR
Roger L. Bagula, May 15 2010
STATUS
approved