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A300605
T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2, 3 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
7
1, 1, 1, 1, 3, 1, 1, 2, 2, 1, 1, 10, 6, 10, 1, 1, 13, 18, 18, 13, 1, 1, 42, 23, 42, 23, 42, 1, 1, 74, 89, 141, 141, 89, 74, 1, 1, 188, 230, 394, 615, 394, 230, 188, 1, 1, 387, 552, 1397, 2394, 2394, 1397, 552, 387, 1, 1, 885, 1555, 4808, 11752, 16629, 11752, 4808, 1555, 885, 1, 1
OFFSET
1,5
COMMENTS
Table starts
.1...1....1.....1......1.......1........1..........1...........1............1
.1...3....2....10.....13......42.......74........188.........387..........885
.1...2....6....18.....23......89......230........552........1555.........4206
.1..10...18....42....141.....394.....1397.......4808.......16894........58420
.1..13...23...141....615....2394....11752......56417......267220......1288938
.1..42...89...394...2394...16629...110249.....729292.....4931949.....33688331
.1..74..230..1397..11752..110249..1056816....9684995....92435041....880584819
.1.188..552..4808..56417..729292..9684995..125507384..1674738412..22241403689
.1.387.1555.16894.267220.4931949.92435041.1674738412.31211394832.583083792885
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = 4*a(n-2) +2*a(n-3) +a(n-5) -3*a(n-6) +a(n-7)
k=3: [order 30] for n>31
EXAMPLE
Some solutions for n=5 k=4
..0..0..0..0. .0..0..1..1. .0..0..1..1. .0..0..1..1. .0..1..1..1
..0..1..1..0. .0..1..0..1. .0..1..0..1. .0..1..0..1. .1..0..1..0
..0..1..0..0. .0..1..1..0. .1..0..0..1. .1..1..1..1. .1..1..0..0
..0..0..1..0. .0..0..0..0. .1..1..1..1. .0..0..0..0. .0..1..0..1
..1..0..0..1. .1..0..0..1. .0..1..1..0. .0..1..0..1. .1..1..1..1
CROSSREFS
Column 2 is A300374.
Sequence in context: A143214 A300380 A300682 * A301330 A175636 A352935
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Mar 09 2018
STATUS
approved