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 A283857 T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than three of its horizontal, diagonal and antidiagonal neighbors. 13
 2, 4, 4, 8, 16, 8, 16, 61, 64, 16, 32, 233, 409, 256, 32, 64, 896, 2776, 2837, 1024, 64, 128, 3444, 19220, 35373, 19776, 4096, 128, 256, 13225, 131617, 456316, 448490, 137459, 16384, 256, 512, 50789, 901397, 5742620, 10741381, 5676420, 955680, 65536, 512 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Table starts ...2.....4.......8........16...........32.............64..............128 ...4....16......61.......233..........896...........3444............13225 ...8....64.....409......2776........19220.........131617...........901397 ..16...256....2837.....35373.......456316........5742620.........72394838 ..32..1024...19776....448490.....10741381......247708452.......5724272337 ..64..4096..137459...5676420....252014450....10634931992.....449942735521 .128.16384..955680..71903903...5921518755...457711375590...35481195059121 .256.65536.6645662.910712188.139111379622.19691576356912.2796411775700471 LINKS R. H. Hardin, Table of n, a(n) for n = 1..221 FORMULA Empirical for column k: k=1: a(n) = 2*a(n-1) k=2: a(n) = 4*a(n-1) k=3: [order 8] k=4: [order 17] k=5: [order 45] Empirical for row n: n=1: a(n) = 2*a(n-1) n=2: a(n) = 3*a(n-1) +a(n-2) +7*a(n-3) +6*a(n-4) n=3: [order 14] n=4: [order 28] n=5: [order 74] EXAMPLE Some solutions for n=4 k=4 ..1..0..0..1. .0..0..1..0. .1..1..1..1. .0..0..0..0. .1..0..1..1 ..0..1..1..0. .1..0..0..0. .0..1..0..0. .0..0..0..1. .1..0..1..1 ..0..1..1..0. .0..1..1..0. .0..0..0..1. .0..0..0..0. .1..0..0..1 ..1..1..0..0. .1..0..0..0. .1..0..0..1. .1..1..0..1. .1..1..0..1 CROSSREFS Column 1 is A000079. Column 2 is A000302. Row 1 is A000079. Sequence in context: A297374 A297102 A283415 * A227442 A282316 A228986 Adjacent sequences:  A283854 A283855 A283856 * A283858 A283859 A283860 KEYWORD nonn,tabl AUTHOR R. H. Hardin, Mar 17 2017 STATUS approved

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Last modified November 29 18:41 EST 2021. Contains 349416 sequences. (Running on oeis4.)