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 A297654 T(n,k)=Number of nXk 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 2 or 3 neighboring 1s. 13
 1, 2, 1, 4, 10, 1, 7, 43, 36, 1, 12, 140, 231, 126, 1, 21, 494, 1073, 1421, 454, 1, 37, 1845, 6838, 11024, 9033, 1632, 1, 65, 6757, 45036, 131044, 113252, 55706, 5854, 1, 114, 24479, 268655, 1580681, 2525244, 1105531, 346032, 21010, 1, 200, 89068, 1617465 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Table starts .1.....2........4..........7...........12.............21................37 .1....10.......43........140..........494...........1845..............6757 .1....36......231.......1073.........6838..........45036............268655 .1...126.....1421......11024.......131044........1580681..........16899640 .1...454.....9033.....113252......2525244.......56630842........1075678445 .1..1632....55706....1105531.....46187510.....1906300826.......63350980838 .1..5854...346032...11089103....864944851....65775301075.....3863740405975 .1.21010..2151932..110654243..16149058068..2265577299182...234680441414485 .1.75412.13364992.1101808354.300870617401.77814433907002.14203234114710492 LINKS R. H. Hardin, Table of n, a(n) for n = 1..219 FORMULA Empirical for column k: k=1: a(n) = a(n-1) k=2: a(n) = 3*a(n-1) +a(n-2) +4*a(n-3) k=3: [order 11] k=4: [order 24] k=5: [order 60] Empirical for row n: n=1: a(n) = 2*a(n-1) -a(n-2) +a(n-3) n=2: a(n) = 3*a(n-1) -2*a(n-2) +13*a(n-3) +6*a(n-4) +12*a(n-5) +12*a(n-6) n=3: [order 17] n=4: [order 38] EXAMPLE Some solutions for n=4 k=4 ..0..1..1..0. .0..0..0..1. .0..1..1..0. .0..0..1..0. .1..1..1..1 ..0..0..0..0. .0..0..1..1. .0..0..0..1. .1..0..0..1. .0..0..0..1 ..1..1..1..1. .0..0..0..0. .1..1..0..0. .0..1..1..0. .1..1..0..0 ..0..1..0..0. .0..0..1..1. .1..1..0..0. .1..0..0..0. .1..1..1..0 CROSSREFS Column 2 is A202796. Row 1 is A005251(n+2). Sequence in context: A071949 A297506 A297720 * A220922 A220993 A219002 Adjacent sequences:  A297651 A297652 A297653 * A297655 A297656 A297657 KEYWORD nonn,tabl AUTHOR R. H. Hardin, Jan 02 2018 STATUS approved

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Last modified December 8 16:28 EST 2021. Contains 349596 sequences. (Running on oeis4.)