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 A318068 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 8
 0, 1, 1, 1, 5, 1, 2, 18, 18, 2, 3, 67, 98, 67, 3, 5, 249, 649, 649, 249, 5, 8, 925, 4003, 7170, 4003, 925, 8, 13, 3437, 25106, 76927, 76927, 25106, 3437, 13, 21, 12770, 156846, 829137, 1405892, 829137, 156846, 12770, 21, 34, 47447, 980960, 8929364, 25994502 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS Table starts ..0.....1.......1..........2............3..............5................8 ..1.....5......18.........67..........249............925.............3437 ..1....18......98........649.........4003..........25106...........156846 ..2....67.....649.......7170........76927.........829137..........8929364 ..3...249....4003......76927......1405892.......25994502........479322719 ..5...925...25106.....829137.....25994502......824452611......26085599617 ..8..3437..156846....8929364....479322719....26085599617....1415459855958 .13.12770..980960...96178466...8844178475...825766558967...76853282341918 .21.47447.6133497.1035919809.163160290206.26137612655323.4172233315256556 LINKS R. H. Hardin, Table of n, a(n) for n = 1..241 FORMULA Empirical for column k: k=1: a(n) = a(n-1) +a(n-2) k=2: a(n) = 3*a(n-1) +3*a(n-2) -a(n-3) -a(n-4) k=3: [order 11] for n>12 k=4: [order 39] EXAMPLE Some solutions for n=5 k=4 ..0..1..1..0. .0..0..1..1. .0..1..0..0. .0..1..1..1. .0..1..1..0 ..1..1..1..0. .1..0..0..0. .1..0..0..1. .1..0..0..1. .0..0..0..1 ..0..1..0..0. .1..1..0..1. .1..0..0..0. .0..0..1..1. .0..1..1..0 ..0..0..0..1. .1..0..0..0. .0..0..1..0. .1..0..0..1. .0..1..0..1 ..1..0..1..0. .0..1..1..1. .1..1..1..0. .1..0..1..0. .0..0..0..1 CROSSREFS Column 1 is A000045(n-1). Sequence in context: A317823 A318430 A318098 * A165449 A019114 A201526 Adjacent sequences: A318065 A318066 A318067 * A318069 A318070 A318071 KEYWORD nonn,tabl AUTHOR R. H. Hardin, Aug 15 2018 STATUS approved

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Last modified June 10 07:34 EDT 2023. Contains 363195 sequences. (Running on oeis4.)