A177848
Triangle, read by rows, T(n, k) = t(k, n-k+1) - t(1, n) + 1 where t(n, m) = (n*m)!*Beta(n, m).
Original entry on oeis.org
1, 1, 1, 1, 3, 1, 1, 55, 55, 1, 1, 1993, 12073, 1993, 1, 1, 120841, 7983241, 7983241, 120841, 1, 1, 11404081, 12454040881, 149448498481, 12454040881, 11404081, 1, 1, 1556750161, 38109367290961, 8688935743482961, 8688935743482961, 38109367290961, 1556750161, 1
Offset: 1
Triangle begins as:
1;
1, 1;
1, 3, 1;
1, 55, 55, 1;
1, 1993, 12073, 1993, 1;
1, 120841, 7983241, 7983241, 120841, 1;
1, 11404081, 12454040881, 149448498481, 12454040881, 11404081, 1;
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t[n_, k_]:= (n*k)!*Beta[n, k];
Table[t[k, n-k+1] - t[1, n] + 1, {n, 12}, {k, n}]//Flatten
-
def t(n, k): return factorial(n*k)*beta(n, k)
flatten([[t(k, n-k+1) - t(1,n) + 1 for k in (1..n)] for n in (1..12)]) # G. C. Greubel, Feb 06 2021
A215286
Number of permutations of 0..floor((n*n-1)/2) on even squares of an n X n array such that each row and column of even squares is increasing.
Original entry on oeis.org
1, 2, 10, 280, 60060, 85765680, 2061378118800, 346915095471584640, 1736278161426147413954880, 62144711688730139887005809020800, 103104526145243794108489566205445861006400
Offset: 1
Some solutions for n=5
..0..x..1..x..2....0..x..2..x..6....0..x..2..x..4....1..x..2..x..6
..x..4..x..7..x....x..1..x..3..x....x..3..x..5..x....x..0..x..8..x
..3..x..6..x..9....5..x..8..x.11....1..x..8..x..9....3..x..5..x.10
..x..5..x.11..x....x..4..x..9..x....x..7..x.10..x....x..9..x.12..x
..8..x.10..x.12....7..x.10..x.12....6..x.11..x.12....4..x..7..x.11
A215289
Number of permutations of 0..floor((n*5-1)/2) on even squares of an n X 5 array such that each row and column of even squares is increasing.
Original entry on oeis.org
1, 10, 140, 2100, 60060, 1051050, 42882840, 814773960, 41227562376, 824551247520, 48236247979920, 999179422441200, 64899082486180800, 1379105502831342000, 96951116849043342600, 2100607531729272423000, 157112712418611824074200, 3456479673209460129632400, 271742147399231010918736320
Offset: 1
Some solutions for n=5:
..0..x..2..x..6....1..x..2..x..6....0..x..3..x..9....0..x..1..x..8
..x..3..x..4..x....x..0..x..4..x....x..2..x..4..x....x..3..x..6..x
..1..x..7..x.10....7..x..9..x.11....1..x..7..x.11....2..x..4..x..9
..x..5..x.11..x....x..3..x..5..x....x..5..x..8..x....x..7..x.10..x
..8..x..9..x.12....8..x.10..x.12....6..x.10..x.12....5..x.11..x.12
A215291
Number of permutations of 0..floor((n*7-1)/2) on even squares of an nX7 array such that each row and column of even squares is increasing.
Original entry on oeis.org
1, 35, 2310, 210210, 42882840, 5703417720, 2061378118800, 337653735859440, 173457547735792320, 32436561426593163840, 21174123919831066023840, 4340695403565368534887200, 3373030378241974592216989200
Offset: 1
Some solutions for n=3
..0..x..3..x..5..x..6....0..x..1..x..2..x..3....1..x..2..x..3..x..5
..x..1..x..8..x.10..x....x..5..x..8..x.10..x....x..0..x..6..x.10..x
..2..x..4..x..7..x..9....4..x..6..x..7..x..9....4..x..7..x..8..x..9
A215293
Number of permutations of 0..floor((n*n-2)/2) on odd squares of an n X n array such that each row and column of odd squares is increasing.
Original entry on oeis.org
1, 2, 6, 280, 23100, 85765680, 577185873264, 346915095471584640, 381134230556959188429120, 62144711688730139887005809020800, 18592619468814454675301397184588597886400, 1236552808693429892089668394551052130596983991526400, 151213938214745201135492692441902799026853717717324113365952000
Offset: 1
Some solutions for n=5
..x..0..x..4..x....x..4..x..6..x....x..1..x..6..x....x..0..x..6..x
..1..x..3..x..7....0..x..1..x..9....0..x..2..x..3....3..x..4..x..9
..x..2..x..5..x....x..5..x..8..x....x..7..x..8..x....x..1..x..7..x
..8..x..9..x.10....2..x..3..x.10....4..x..5..x.11....5..x..8..x.11
..x..6..x.11..x....x..7..x.11..x....x..9..x.10..x....x..2..x.10..x
A215294
Number of permutations of 0..floor((n*3-2)/2) on odd squares of an n X 3 array such that each row and column of odd squares is increasing.
Original entry on oeis.org
1, 3, 6, 30, 70, 420, 1050, 6930, 18018, 126126, 336336, 2450448, 6651216, 49884120, 137181330, 1051723530, 2921454250, 22787343150, 63804560820, 504636071940, 1422156202740, 11377249621920, 32235540595440, 260363981732400
Offset: 1
Some solutions for n=5:
x 1 x x 0 x x 0 x x 4 x x 0 x x 1 x x 1 x
0 x 5 2 x 4 2 x 5 0 x 2 1 x 2 0 x 5 0 x 3
x 3 x x 1 x x 1 x x 5 x x 3 x x 2 x x 2 x
2 x 6 3 x 6 3 x 6 1 x 3 4 x 6 3 x 6 4 x 5
x 4 x x 5 x x 4 x x 6 x x 5 x x 4 x x 6 x
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a := n -> `if`(irem(n, 2) = 0, ((1/2)*n+1)*factorial((3/2)*n)/ (factorial((1/2)*n+1)^2*factorial((1/2)*n)), factorial((3/2)*n+3/2)/ (factorial((1/2)*n+1/2)^3*((9/2)*n+3/2))): # Peter Luschny, Sep 30 2018
A215295
Number of permutations of 0..floor((n*5-2)/2) on odd squares of an nX5 array such that each row and column of odd squares is increasing.
Original entry on oeis.org
1, 10, 70, 2100, 23100, 1051050, 14294280, 814773960, 12547518984, 824551247520, 13781785137120, 999179422441200, 17699749768958400, 1379105502831342000, 25513451802379827000, 2100607531729272423000, 40191624107086745693400
Offset: 1
Some solutions for n=5
..x..2..x..6..x....x..1..x..5..x....x..0..x..5..x....x..0..x..2..x
..0..x..3..x..4....0..x..2..x..7....2..x..4..x.10....3..x..6..x..8
..x..5..x.10..x....x..3..x..9..x....x..1..x..8..x....x..1..x..7..x
..1..x..7..x..8....4..x..6..x.11....6..x..7..x.11....4..x..9..x.11
..x..9..x.11..x....x..8..x.10..x....x..3..x..9..x....x..5..x.10..x
A215296
Number of permutations of 0..floor((n*7-2)/2) on odd squares of an nX7 array such that each row and column of odd squares is increasing.
Original entry on oeis.org
1, 35, 1050, 210210, 14294280, 5703417720, 577185873264, 337653735859440, 43364386933948080, 32436561426593163840, 4886336289191784467040, 4340695403565368534887200, 733267473530864041786302000
Offset: 1
Some solutions for n=3
..x..0..x..1..x..3..x....x..0..x..2..x..5..x....x..0..x..1..x..3..x
..2..x..4..x..6..x..9....3..x..6..x..8..x..9....5..x..6..x..8..x..9
..x..5..x..7..x..8..x....x..1..x..4..x..7..x....x..2..x..4..x..7..x
A378173
Array read by antidiagonals: T(n,k) is the number of proper antichain partitions of the rectangular poset of size n X k.
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 1, 5, 5, 1, 1, 14, 38, 14, 1, 1, 42, 372, 372, 42, 1, 1, 132, 4282, 14606, 4282, 132, 1, 1, 429, 55149
Offset: 1
Array begins:
=====================================================================
n/k | 1 2 3 4 5 6 ...
----+----------------------------------------------------------------
1 | 1 1 1 1 1 1 ...
2 | 1 2 5 14 42 132 ...
3 | 1 5 38 372 4282 55149 ...
4 | 1 14 372 14606 ...
5 | 1 42 4282 ...
6 | 1 132 55149 ...
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