cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A181206 T(n,k) = number of n X k matrices containing a permutation of 1..n*k moving each element at most to a neighboring position.

Original entry on oeis.org

1, 2, 2, 3, 9, 3, 5, 32, 32, 5, 8, 121, 229, 121, 8, 13, 450, 1845, 1845, 450, 13, 21, 1681, 14320, 32000, 14320, 1681, 21, 34, 6272, 112485, 535229, 535229, 112485, 6272, 34, 55, 23409, 880163, 9049169, 19114420, 9049169, 880163, 23409, 55, 89, 87362
Offset: 1

Views

Author

R. H. Hardin, Oct 10 2010

Keywords

Comments

Also, the number of perfect matchings in the graph P_2 X P_k X P_n. - Andrew Howroyd, May 17 2017

Examples

			Table starts:
..1......2.........3............5................8..................13
..2......9........32..........121..............450................1681
..3.....32.......229.........1845............14320..............112485
..5....121......1845........32000...........535229.............9049169
..8....450.....14320.......535229.........19114420...........692276437
.13...1681....112485......9049169........692276437.........53786626921
.21...6272....880163....152526845......24972353440.......4161756233501
.34..23409...6895792...2573281769.....901990734650.....322462050747008
.55..87362..54003765..43402320448...32567565264292...24976513162427653
.89.326041.422983905.732106008249.1176040842289105.1934824269280528177
...
All solutions for 3X2
..1..2....1..2....1..2....1..2....1..2....1..2....1..2....1..2....1..2....1..4
..3..4....4..3....4..3....4..6....3..4....3..6....5..4....5..3....5..6....3..2
..5..6....5..6....6..5....3..5....6..5....5..4....3..6....6..4....3..4....5..6
...
..1..4....1..4....2..1....2..1....2..1....2..1....2..1....2..1....2..1....2..1
..3..2....5..2....4..3....4..3....4..6....3..4....3..4....3..6....5..4....5..3
..6..5....3..6....5..6....6..5....3..5....5..6....6..5....5..4....3..6....6..4
...
..2..1....2..4....2..4....2..4....3..1....3..1....3..1....3..2....3..2....3..2
..5..6....1..3....1..3....1..6....4..2....4..2....5..2....1..4....1..4....1..6
..3..4....5..6....6..5....3..5....5..6....6..5....6..4....5..6....6..5....5..4
...
..3..4....3..4
..1..2....1..2
..5..6....6..5
		

Crossrefs

Main diagonal gives A181205.