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A090665 Triangle read by rows: T(n,k) = number of preferential arrangements of n things beginning with k. 0
1, 2, 1, 6, 5, 2, 26, 25, 18, 6, 150, 149, 134, 84, 24, 1082, 1081, 1050, 870, 480, 120, 9366, 9365, 9302, 8700, 6600, 3240, 720, 94586, 94585, 94458, 92526, 82320, 57120, 25200, 5040, 1091670, 1091669, 1091414, 1085364, 1038744, 871920, 554400, 221760, 40320 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The rows are the reverses of the rows of A054255.

Row sums give A000670.

Column 1 is A000629. - Joerg Arndt, Dec 08 2014

LINKS

Table of n, a(n) for n=1..45.

EXAMPLE

Triangle starts:

01: 1;

02: 2, 1;

03: 6, 5, 2;

04: 26, 25, 18, 6;

05: 150, 149, 134, 84, 24;

06: 1082, 1081, 1050, 870, 480, 120;

07: 9366, 9365, 9302, 8700, 6600, 3240, 720;

08: 94586, 94585, 94458, 92526, 82320, 57120, 25200, 5040;

09: 1091670, 1091669, 1091414, 1085364, 1038744, 871920, 554400, 221760, 40320;

10: 14174522, 14174521, 14174010, 14155350, 13950720, 12930120, 10190880, 5957280, 2177280, 362880;

...

PROG

The program is written in a variant of APL called J, a product of JSoftware. Since so few people know J, I'll not display the functions used to produce the sequence.

CROSSREFS

Cf. A054255, A008277, A028246.

Sequence in context: A113381 A228175 A118980 * A021826 A159927 A176443

Adjacent sequences:  A090662 A090663 A090664 * A090666 A090667 A090668

KEYWORD

nonn,tabl

AUTHOR

Eugene McDonnell (eemcd(AT)mac.com), Dec 16 2003

EXTENSIONS

Corrected by Alois P. Heinz, Dec 08 2014

STATUS

approved

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Last modified December 3 07:27 EST 2016. Contains 278698 sequences.