login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A304901
T(n,k) = Number of n X k 0..1 arrays with every element unequal to 1, 2, 3, 4 or 7 king-move adjacent elements, with upper left element zero.
7
0, 1, 1, 1, 7, 1, 2, 23, 23, 2, 3, 86, 62, 86, 3, 5, 313, 330, 330, 313, 5, 8, 1145, 1249, 2373, 1249, 1145, 8, 13, 4184, 5562, 13954, 13954, 5562, 4184, 13, 21, 15293, 23101, 88308, 107723, 88308, 23101, 15293, 21, 34, 55895, 99064, 546357, 946723, 946723, 546357
OFFSET
1,5
COMMENTS
Table starts
..0.....1......1........2.........3...........5............8.............13
..1.....7.....23.......86.......313........1145.........4184..........15293
..1....23.....62......330......1249........5562........23101..........99064
..2....86....330.....2373.....13954.......88308.......546357........3395402
..3...313...1249....13954....107723......946723......8143342.......69406724
..5..1145...5562....88308....946723....11067544....132134627.....1529832969
..8..4184..23101...546357...8143342...132134627...2256313057....36576467823
.13.15293..99064..3395402..69406724..1529832969..36576467823...816589152784
.21.55895.418753.21113828.599014812.18095801753.611064999079.18937183868022
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2);
k=2: a(n) = 3*a(n-1) +a(n-2) +4*a(n-3) +4*a(n-4);
k=3: [order 15] for n>16;
k=4: [order 46] for n>48.
EXAMPLE
Some solutions for n=5, k=4
..0..0..1..0. .0..1..1..1. .0..0..0..1. .0..1..1..1. .0..0..0..1
..0..1..0..0. .1..1..1..0. .1..0..0..0. .0..1..0..1. .1..1..0..0
..1..1..1..0. .1..1..1..0. .1..0..0..1. .0..1..1..0. .0..0..0..1
..0..1..1..0. .0..1..1..0. .0..1..1..1. .0..1..1..1. .1..1..0..1
..0..0..0..1. .1..0..1..1. .0..1..1..0. .0..1..0..0. .0..0..0..1
CROSSREFS
Column 1 is A000045(n-1).
Column 2 is A303890.
Sequence in context: A317436 A303896 A305288 * A316583 A304597 A316383
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, May 20 2018
STATUS
approved