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A300612
T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3 or 5 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, 1432, 2347, 1432, 307, 8, 13, 981, 7514, 19532, 19532, 7514, 981, 13, 21, 3137, 39330, 164619, 263468, 164619, 39330, 3137, 21, 34, 10034, 205958, 1387896, 3567928, 3567928
OFFSET
1,5
COMMENTS
Table starts
..0.....1.......1........2..........3............5..............8
..1.....3......10.......30.........96..........307............981
..1....10......53......277.......1432.........7514..........39330
..2....30.....277.....2347......19532.......164619........1387896
..3....96....1432....19532.....263468......3567928.......48279880
..5...307....7514...164619....3567928.....77669371.....1693172810
..8...981...39330..1387896...48279880...1693172810....59556673490
.13..3137..205958.11697909..653282566..36914891724..2093683166397
.21.10034.1078479.98591087.8839456244.804586936082.73570793306416
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 17] for n>18
k=4: [order 72] for n>73
EXAMPLE
Some solutions for n=5 k=4
..0..0..0..0. .0..1..1..0. .0..0..0..1. .0..1..0..0. .0..0..0..0
..0..1..0..1. .0..1..0..0. .1..0..0..1. .0..1..1..0. .0..1..1..0
..0..1..0..1. .1..0..1..0. .1..1..0..0. .0..0..1..1. .0..0..1..1
..0..1..0..0. .1..0..1..0. .1..0..1..0. .0..1..0..1. .1..0..0..1
..1..0..1..1. .0..0..0..0. .0..1..1..0. .1..1..0..0. .1..1..0..0
CROSSREFS
Column 1 is A000045(n-1).
Column 2 is A300421.
Sequence in context: A301669 A300427 A300689 * A301354 A229187 A126226
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Mar 09 2018
STATUS
approved