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.

A267724 T(n,k)=Number of nXk arrays containing k copies of 0..n-1 with every element equal to at least one horizontal neighbor and the top left element equal to 0.

Original entry on oeis.org

0, 1, 0, 1, 1, 0, 1, 1, 2, 0, 1, 3, 2, 6, 0, 1, 5, 30, 6, 24, 0, 1, 12, 58, 630, 24, 120, 0, 1, 26, 588, 1398, 22680, 120, 720, 0, 1, 60, 2388, 93672, 55896, 1247400, 720, 5040, 0, 1, 143, 17456, 609264, 33807456, 3353880, 97297200, 5040, 40320, 0, 1, 353, 102874
Offset: 1

Views

Author

R. H. Hardin, Jan 20 2016

Keywords

Comments

Table starts
.0......1.....1...........1.........1...........1.........1........1.........1
.0......1.....1...........3.........5..........12........26.......60.......143
.0......2.....2..........30........58.........588......2388....17456....102874
.0......6.....6.........630......1398.......93672....609264.20702760.279681294
.0.....24....24.......22680.....55896....33807456.331295040
.0....120...120.....1247400...3353880.22933860480
.0....720...720....97297200.281725200
.0...5040..5040.10216206000
.0..40320.40320
.0.362880

Examples

			Some solutions for n=4 k=4
..0..0..2..2....0..0..0..0....0..0..1..1....0..0..2..2....0..0..3..3
..2..2..0..0....3..3..3..3....3..3..2..2....1..1..0..0....1..1..2..2
..1..1..3..3....2..2..1..1....0..0..2..2....3..3..2..2....1..1..2..2
..3..3..1..1....2..2..1..1....3..3..1..1....3..3..1..1....0..0..3..3
		

Crossrefs

Column 2 and column 3 are A000142(n-1).
Column 4 is A007019(n-1).