A338368 Triangle of number of 312-avoiding reduced valid hook configurations with n hooks that are on permutations with 2n + k points, for n=1 and 1<=k<=n.

1, 3, 5, 14, 51, 42, 84, 485, 849, 462, 594, 4743, 13004, 14819, 6006, 4719, 48309, 182311, 322789, 271452, 87516, 40898, 511607, 2472322, 5999489, 7794646, 5182011, 13856

Offset

1,2

Links

Table of n, a(n) for n=1..28.

Ilani Axelrod-Freed, 312-Avoiding Reduced Valid Hook Configurations and Duck Words, arXiv:2010.11834 [math.CO], 2020.

Maya Sankar, Further Bijections to Pattern-Avoiding Valid Hook Configurations, arXiv:1910.08895 [math.CO], 2019.

Example

Triangle begins
  1
  3 5
  14 51 42
  84 485 849 462
  594 4743 13004 14819 6006
  4719 48309 182311 322789 271452 87516
  40898 511607 2472322 5999489 7794646 5182011 13856

Crossrefs

Cf. A005700 (1st column), A005789 (right diagonal).

Sequence in context: A006395 A078718 A081393 * A129326 A167553 A370612

Adjacent sequences: A338365 A338366 A338367 * A338369 A338370 A338371

Keyword

nonn,tabl,more

Author

Michel Marcus, Oct 23 2020

Status

approved