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A301354
T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
7
0, 1, 1, 1, 3, 1, 2, 10, 10, 2, 3, 30, 53, 30, 3, 5, 96, 277, 277, 96, 5, 8, 307, 1433, 2349, 1433, 307, 8, 13, 981, 7522, 19561, 19561, 7522, 981, 13, 21, 3137, 39390, 165010, 264054, 165010, 39390, 3137, 21, 34, 10034, 206370, 1392131, 3579171, 3579171
OFFSET
1,5
COMMENTS
Table starts
..0.....1.......1........2..........3............5..............8
..1.....3......10.......30.........96..........307............981
..1....10......53......277.......1433.........7522..........39390
..2....30.....277.....2349......19561.......165010........1392131
..3....96....1433....19561.....264054......3579171.......48476633
..5...307....7522...165010....3579171.....78012336.....1702789144
..8...981...39390..1392131...48476633...1702789144....59990521481
.13..3137..206370.11741731..656551657..37169645074..2112136719464
.21.10034.1081141.99032014.8891966361.811102103620.74331048515102
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) -3*a(n-4) -2*a(n-5) -a(n-6) for n>7
k=3: [order 18] for n>20
k=4: [order 72] for n>73
EXAMPLE
Some solutions for n=5 k=4
..0..1..1..1. .0..0..1..0. .0..0..1..1. .0..1..1..1. .0..0..0..1
..0..0..0..0. .1..0..1..0. .1..1..1..1. .0..0..1..0. .1..1..0..1
..0..1..0..0. .1..0..0..0. .0..0..1..0. .0..1..0..1. .1..1..0..0
..0..1..1..0. .0..1..1..1. .0..1..0..1. .0..0..0..1. .0..1..1..0
..0..1..0..0. .0..1..0..0. .1..1..1..1. .1..1..0..0. .0..1..1..0
CROSSREFS
Column 1 is A000045(n-1).
Column 2 is A300421.
Sequence in context: A300427 A300689 A300612 * A229187 A126226 A307665
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Mar 19 2018
STATUS
approved