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 A297431 T(n,k)=Number of nXk 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2 neighboring 1s. 13
 1, 1, 1, 1, 2, 1, 1, 7, 3, 1, 1, 12, 14, 4, 1, 1, 18, 26, 22, 6, 1, 1, 33, 43, 42, 68, 9, 1, 1, 73, 109, 105, 183, 163, 13, 1, 1, 139, 301, 349, 535, 513, 320, 19, 1, 1, 244, 649, 1057, 2430, 1673, 1085, 782, 28, 1, 1, 449, 1332, 2834, 12005, 11345, 5108, 3332, 1889, 41, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS Table starts .1..1....1....1.....1.......1........1.........1..........1...........1 .1..2....7...12....18......33.......73.......139........244.........449 .1..3...14...26....43.....109......301.......649.......1332........3124 .1..4...22...42...105.....349.....1057......2834.......8216.......24556 .1..6...68..183...535....2430....12005.....45977.....182298......793315 .1..9..163..513..1673...11345....76692....369339....1884628....11192445 .1.13..320.1085..5108...50127...431723...2741816...19713343...158831909 .1.19..782.3332.19690..267505..3338387..28588498..275287217..3091469216 .1.28.1889.9744.66529.1348969.23694911.264853947.3362921639.52055334454 LINKS R. H. Hardin, Table of n, a(n) for n = 1..337 FORMULA Empirical for column k: k=1: a(n) = a(n-1) k=2: a(n) = a(n-1) +a(n-3) k=3: a(n) = a(n-1) +7*a(n-3) +a(n-5) -4*a(n-6) k=4: a(n) = a(n-1) +12*a(n-3) +2*a(n-4) +2*a(n-5) -7*a(n-6) -a(n-7) k=5: [order 20] k=6: [order 37] k=7: [order 81] Empirical for row n: n=1: a(n) = a(n-1) n=2: a(n) = a(n-1) +a(n-3) +4*a(n-4) n=3: a(n) = a(n-1) +3*a(n-3) +8*a(n-4) +a(n-5) -a(n-6) n=4: [order 12] n=5: [order 29] n=6: [order 59] EXAMPLE Some solutions for n=5 k=4 ..0..0..1..1. .0..1..1..1. .0..0..1..1. .0..0..0..0. .0..0..0..0 ..0..0..1..1. .0..0..1..0. .0..0..1..1. .0..0..0..0. .0..0..1..0 ..0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..1..1. .0..1..0..1 ..0..1..1..1. .0..1..1..0. .1..1..0..0. .0..1..1..0. .0..0..1..0 ..0..0..1..0. .1..1..0..0. .1..1..0..0. .0..0..0..0. .0..0..0..0 CROSSREFS Column 2 is A000930(n+1). Sequence in context: A247450 A178234 A259175 * A301922 A144510 A143670 Adjacent sequences:  A297428 A297429 A297430 * A297432 A297433 A297434 KEYWORD nonn,tabl AUTHOR R. H. Hardin, Dec 30 2017 STATUS approved

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Last modified April 17 03:44 EDT 2021. Contains 343059 sequences. (Running on oeis4.)