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A272643
Irregular triangle read by rows, enumerating permutations of "specification (321^{n-5})".
0
1, 6, 3, 1, 17, 33, 9, 1, 40, 184, 168, 27, 1, 87, 792, 1592, 807, 81
OFFSET
5,2
COMMENTS
Related to Simon Newcomb's problem.
It would be nice to have a more precise definition. See Kaplansky-Riordan, Section 7.
LINKS
Irving Kaplansky and John Riordan, The problem of the rooks and its applications, Duke Mathematical Journal 13.2 (1946): 259-268.
Irving Kaplansky and John Riordan, The problem of the rooks and its applications, in Combinatorics, Duke Mathematical Journal, 13.2 (1946): 259-268. [Annotated scanned copy]
EXAMPLE
The triangle starts at row n=5:
1, 6, 3,
1, 17, 33, 9,
1, 40, 184, 168, 27,
1, 87, 792, 1592, 807, 81,
...
CROSSREFS
Sequence in context: A192741 A240264 A119743 * A243424 A182227 A108451
KEYWORD
nonn,tabf,more
AUTHOR
N. J. A. Sloane, May 07 2016
STATUS
approved