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.

A297802 T(n,k) = Number of n X k 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2, 3 or 5 neighboring 1's.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 1, 11, 4, 1, 1, 24, 37, 7, 1, 1, 38, 100, 108, 14, 1, 1, 105, 293, 422, 533, 31, 1, 1, 381, 1320, 2195, 2936, 2434, 69, 1, 1, 1067, 6215, 16006, 23781, 17899, 10287, 155, 1, 1, 2676, 24879, 115773, 320168, 231921, 104985, 45968, 354, 1, 1, 7533, 99567
Offset: 1

Views

Author

R. H. Hardin, Jan 06 2018

Keywords

Comments

Table starts
.1...1......1.......1.........1...........1.............1...............1
.1...2.....11......24........38.........105...........381............1067
.1...4.....37.....100.......293........1320..........6215...........24879
.1...7....108.....422......2195.......16006........115773..........738989
.1..14....533....2936.....23781......320168.......4340367........46828204
.1..31...2434...17899....231921.....5511367.....123361724......2122878239
.1..69..10287..104985...2174696....91376524....3420197908.....94927605755
.1.155..45968..645568..21427001..1587468720..102189481612...4611250894511
.1.354.207906.3978117.209042911.27421636815.2993486726263.218072722004943

Examples

			Some solutions for n=5, k=4
..0..1..1..1. .0..0..0..0. .0..1..1..1. .0..1..0..0. .0..1..1..0
..0..1..1..0. .0..1..1..1. .0..0..1..1. .1..1..1..0. .0..1..1..1
..0..0..1..0. .0..0..1..1. .1..1..0..1. .0..0..0..1. .0..1..1..1
..1..1..0..0. .0..1..1..1. .0..1..1..1. .0..1..1..0. .1..1..0..0
..1..1..0..0. .0..0..1..0. .0..1..1..0. .1..1..0..0. .0..0..0..0
		

Crossrefs

Column 2 is A202973.
Row 2 is A297545.

Formula

Empirical for column k:
k=1: a(n) = a(n-1),
k=2: a(n) = 3*a(n-1) -2*a(n-2) +2*a(n-3) -2*a(n-4) -a(n-5),
k=3: [order 15],
k=4: [order 37],
k=5: [order 95].
Empirical for row n:
n=1: a(n) = a(n-1),
n=2: a(n) = 3*a(n-1) -2*a(n-2) +5*a(n-3) +6*a(n-4) -16*a(n-5) -12*a(n-6),
n=3: [order 21],
n=4: [order 55].