A179456 - OEIS

A179456

Triangle read by rows: number of permutation trees of power n and height <= n - k.

1, 1, 2, 1, 6, 5, 1, 24, 23, 9, 1, 120, 119, 68, 14, 1, 720, 719, 517, 152, 20, 1, 5040, 5039, 4163, 1581, 292, 27, 1, 40320, 40319, 36180, 16776, 3917, 508, 35, 1, 362880, 362879, 341733, 186030, 52029, 8489, 823, 44, 1

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OFFSET

0,3

COMMENTS

Partial row sums of A179454 starting from the diagonal. Special case: A179456(n,n-2) = A000096(n) for n > 1.

LINKS

Table of n, a(n) for n=0..45.

Peter Luschny, Permutation trees.

EXAMPLE

2, 1,

6, 5, 1,

24, 23, 9, 1,

120, 119, 68, 14, 1,

720, 719, 517, 152, 20, 1,

5040, 5039, 4163, 1581, 292, 27, 1,

40320, 40319, 36180, 16776, 3917, 508, 35, 1,

362880, 362879, 341733, 186030, 52029, 8489, 823, 44, 1

CROSSREFS

Cf. A179454, A179455.

Sequence in context: A116395 A159924 A133367 * A214152 A121575 A121576

Adjacent sequences: A179453 A179454 A179455 * A179457 A179458 A179459

KEYWORD

nonn,tabf

AUTHOR

Peter Luschny, Aug 11 2010

STATUS

approved