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 A297720 T(n,k)=Number of nXk 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 2 or 4 neighboring 1s. 13
 1, 2, 1, 4, 10, 1, 7, 34, 29, 1, 12, 83, 145, 87, 1, 21, 258, 523, 747, 280, 1, 37, 865, 2717, 4212, 4090, 876, 1, 65, 2651, 14462, 36981, 34319, 21116, 2735, 1, 114, 8041, 68919, 336653, 512354, 268630, 110551, 8583, 1, 200, 25114, 332306, 2699832, 8103241 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Table starts .1.....2.......4.........7..........12............21..............37 .1....10......34........83.........258...........865............2651 .1....29.....145.......523........2717.........14462...........68919 .1....87.....747......4212.......36981........336653.........2699832 .1...280....4090.....34319......512354.......8103241.......107787351 .1...876...21116....268630.....6812856.....183324631......4021047904 .1..2735..110551...2139403....91994155....4238895126....154327332017 .1..8583..582755..17031173..1242370107...98184350818...5920531350715 .1.26900.3055652.135252357.16741579726.2265008802005.226188909640209 LINKS R. H. Hardin, Table of n, a(n) for n = 1..180 FORMULA Empirical for column k: k=1: a(n) = a(n-1) k=2: a(n) = 2*a(n-1) +2*a(n-2) +5*a(n-3) -a(n-5) -a(n-6) k=3: [order 13] k=4: [order 42] k=5: [order 87] Empirical for row n: n=1: a(n) = 2*a(n-1) -a(n-2) +a(n-3) n=2: a(n) = 4*a(n-1) -3*a(n-2) +3*a(n-3) -2*a(n-4) -24*a(n-5) +24*a(n-6) n=3: [order 18] n=4: [order 51] EXAMPLE Some solutions for n=4 k=4 ..0..1..0..1. .1..1..0..0. .1..0..1..0. .0..0..1..0. .0..0..1..1 ..0..0..1..1. .0..1..0..0. .0..1..1..0. .0..0..0..1. .0..0..1..0 ..0..1..0..0. .0..1..0..0. .1..1..0..0. .1..1..1..1. .1..0..0..0 ..1..0..0..0. .1..1..0..0. .1..0..1..1. .0..1..0..0. .1..1..0..0 CROSSREFS Column 2 is A295525. Row 1 is A005251(n+2). Sequence in context: A100229 A071949 A297506 * A297654 A220922 A220993 Adjacent sequences:  A297717 A297718 A297719 * A297721 A297722 A297723 KEYWORD nonn,tabl AUTHOR R. H. Hardin, Jan 04 2018 STATUS approved

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Last modified September 17 19:12 EDT 2019. Contains 327137 sequences. (Running on oeis4.)