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 A303084 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2, 3, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 12
 1, 1, 2, 1, 2, 4, 1, 12, 2, 8, 1, 20, 32, 3, 16, 1, 72, 29, 112, 6, 32, 1, 168, 258, 90, 416, 10, 64, 1, 496, 432, 1455, 304, 1512, 21, 128, 1, 1296, 2525, 3667, 11767, 1054, 5472, 42, 256, 1, 3616, 6313, 33152, 34430, 84474, 4182, 19904, 86, 512, 1, 9760, 30188, 157838 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Table starts ...1..1.....1.....1........1.........1............1.............1 ...2..2....12....20.......72.......168..........496..........1296 ...4..2....32....29......258.......432.........2525..........6313 ...8..3...112....90.....1455......3667........33152........157838 ..16..6...416...304....11767.....34430.......636070.......4585419 ..32.10..1512..1054....84474....409478.....13375327.....170974652 ..64.21..5472..4182...615471...4862916....266882021....5924274499 .128.42.19904.17369..4647197..60442630...5754725245..218955384065 .256.86.72396.75377.35089147.764631608.125608726910.8100166904419 LINKS R. H. Hardin, Table of n, a(n) for n = 1..180 FORMULA Empirical for column k: k=1: a(n) = 2*a(n-1) k=2: a(n) = 2*a(n-1) +a(n-2) -a(n-3) -2*a(n-4) +a(n-5) k=3: [order 11] k=4: [order 56] for n>57 Empirical for row n: n=1: a(n) = a(n-1) n=2: a(n) = 2*a(n-1) +4*a(n-2) -4*a(n-3) -4*a(n-4) n=3: [order 17] for n>18 n=4: [order 67] for n>68 EXAMPLE Some solutions for n=5 k=4 ..0..0..0..1. .0..1..1..1. .0..0..1..1. .0..1..1..1. .0..0..0..1 ..0..0..0..1. .1..1..1..1. .0..0..1..1. .1..1..1..1. .1..0..0..1 ..0..1..0..1. .0..0..0..0. .1..0..0..0. .0..1..0..1. .1..0..0..1 ..0..0..0..0. .0..0..0..0. .1..0..0..1. .1..1..1..1. .0..0..0..1 ..0..0..0..1. .0..0..0..0. .0..0..0..1. .0..1..1..1. .1..0..0..1 CROSSREFS Column 1 is A000079(n-1). Column 2 is A240513(n-2). Row 2 is A302368. Sequence in context: A302460 A303242 A302367 * A302889 A303624 A121439 Adjacent sequences:  A303081 A303082 A303083 * A303085 A303086 A303087 KEYWORD nonn,tabl AUTHOR R. H. Hardin, Apr 18 2018 STATUS approved

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Last modified December 5 20:39 EST 2021. Contains 349558 sequences. (Running on oeis4.)