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A104443
Square of P(n,t) read by antidiagonals. P(n,t) = number of ways to split [t*n] into n arithmetic progressions each with t terms.
20
1, 1, 1, 1, 3, 1, 1, 2, 15, 1, 1, 2, 5, 105, 1, 1, 2, 4, 15, 945, 1, 1, 2, 4, 11, 55, 10395, 1, 1, 2, 4, 10, 23, 232, 135135, 1, 1, 2, 4, 10, 21, 68, 1161, 2027025, 1, 1, 2, 4, 10, 20, 59, 161, 6643, 34459425, 1, 1, 2, 4, 10, 20, 57, 125, 488, 44566, 654729075, 1
OFFSET
1,5
EXAMPLE
Square array begins:
1, 1, 1, 1, 1, 1, 1, 1, 1, ...
1, 3, 2, 2, 2, 2, 2, 2, 2, ...
1, 15, 5, 4, 4, 4, 4, 4, 4, ...
1, 105, 15, 11, 10, 10, 10, 10, 10, ...
1, 945, 55, 23, 21, 20, 20, 20, 20, ...
1, 10395, 232, 68, 59, 57, 56, 56, 56, ...
1, 135135, 1161, 161, 125, 119, 117, 116, 116, ...
1, 2027025, 6643, 488, 349, 329, 323, 321, 320, ...
1, 34459425, 44566, 1249, 848, 760, 745, 739, 737, ...
...
CROSSREFS
Cf. A104429-A104442. P(1, _)=P(_, 1) = A000012, P(_, 2) = A001147.
Sequence in context: A328901 A362019 A016564 * A218489 A218332 A322506
KEYWORD
nonn,tabl
AUTHOR
Jonas Wallgren, Mar 17 2005
EXTENSIONS
More terms from Alois P. Heinz, Nov 18 2020
STATUS
approved