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A300506
T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
8
1, 2, 2, 3, 3, 3, 5, 2, 2, 5, 8, 3, 4, 3, 8, 13, 6, 7, 7, 6, 13, 21, 6, 6, 20, 6, 6, 21, 34, 11, 17, 32, 32, 17, 11, 34, 55, 26, 34, 68, 56, 68, 34, 26, 55, 89, 43, 57, 191, 208, 208, 191, 57, 43, 89, 144, 82, 80, 504, 546, 1162, 546, 504, 80, 82, 144, 233, 178, 164, 1353, 2006
OFFSET
1,2
COMMENTS
Table starts
..1..2..3....5....8....13.....21......34.......55........89........144
..2..3..2....3....6.....6.....11......26.......43........82........178
..3..2..4....7....6....17.....34......57.......80.......164........302
..5..3..7...20...32....68....191.....504.....1353......4033......11685
..8..6..6...32...56...208....546....2006.....5835.....18466......58308
.13..6.17...68..208..1162...4067...20265....88836....420674....1978897
.21.11.34..191..546..4067..17412..112660...634311...3789374...21768434
.34.26.57..504.2006.20265.112660.1045409..7841480..64468772..513205097
.55.43.80.1353.5835.88836.634311.7841480.76908966.836417456.8738195507
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2)
k=2: a(n) = 2*a(n-1) -a(n-2) +4*a(n-3) -4*a(n-4) +a(n-5) -2*a(n-6) +a(n-7)
k=3: [order 26] for n>31
k=4: [order 93] for n>103
EXAMPLE
Some solutions for n=5 k=4
..0..1..0..1. .0..1..0..0. .0..1..0..1. .0..0..0..1. .0..1..0..1
..0..1..1..0. .0..0..0..0. .0..0..1..0. .1..0..0..0. .0..1..1..0
..1..1..0..1. .0..1..1..0. .0..0..0..1. .1..1..0..0. .1..0..1..1
..1..0..0..1. .0..0..0..0. .1..0..0..1. .1..1..0..0. .0..1..1..1
..1..0..0..0. .0..0..1..0. .1..0..0..0. .1..1..1..0. .1..0..0..1
CROSSREFS
Column 1 is A000045(n+1).
Sequence in context: A110876 A324019 A275378 * A300888 A300944 A301498
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Mar 07 2018
STATUS
approved