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A130469 Triangular array read by rows: T(j,k) = k*(j-k)! for k < j, T(j,k) = 1 for k = j; 1 <= k <= j. 4
1, 1, 1, 2, 2, 1, 6, 4, 3, 1, 24, 12, 6, 4, 1, 120, 48, 18, 8, 5, 1, 720, 240, 72, 24, 10, 6, 1, 5040, 1440, 360, 96, 30, 12, 7, 1, 40320, 10080, 2160, 480, 120, 36, 14, 8, 1, 362880, 80640, 15120, 2880, 600, 144, 42, 16, 9, 1, 3628800, 725760, 120960, 20160, 3600 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

T is also defined in A129867, which gives row sums of T.

LINKS

Table of n, a(n) for n=1..60.

EXAMPLE

First seven rows of T are

[ 1 ]

[ 1, 1 ]

[ 2, 2, 1 ]

[ 6, 4, 3, 1 ]

[ 24, 12, 6, 4, 1 ]

[ 120, 48, 18, 8, 5, 1 ]

[ 720, 240, 72, 24, 10, 6, 1 ]

PROG

(MAGMA) m:=11; &cat[ [ k*Factorial(j-k): k in [1..j-1] ] cat [ 1 ]: j in [1..m] ];

CROSSREFS

Cf. A129867, A130470 (antidiagonal sums), A130471 (first differences of antidiagonal sums).

Sequence in context: A065052 A128308 A109152 * A106381 A064784 A174302

Adjacent sequences:  A130466 A130467 A130468 * A130470 A130471 A130472

KEYWORD

nonn,tabl

AUTHOR

Klaus Brockhaus, May 28 2007

STATUS

approved

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Last modified December 6 22:42 EST 2021. Contains 349567 sequences. (Running on oeis4.)