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 A303624 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2, 3, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 12
 1, 1, 2, 1, 2, 4, 1, 12, 2, 8, 1, 20, 38, 3, 16, 1, 72, 68, 148, 6, 32, 1, 168, 362, 325, 616, 10, 64, 1, 496, 1283, 3591, 1870, 2520, 21, 128, 1, 1296, 5411, 19467, 37910, 10741, 10288, 42, 256, 1, 3616, 22516, 160807, 350410, 398859, 62207, 42100, 86, 512, 1, 9760 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Table starts ...1..1......1.......1.........1...........1.............1................1 ...2..2.....12......20........72.........168...........496.............1296 ...4..2.....38......68.......362........1283..........5411............22516 ...8..3....148.....325......3591.......19467........160807..........1173612 ..16..6....616....1870.....37910......350410.......5249045.........70522741 ..32.10...2520...10741....398859.....6446485.....179884814.......4470005178 ..64.21..10288...62207...4288358...122517773....6323564388.....290118140045 .128.42..42100..363485..46208517..2348299355..224091914399...18955122420980 .256.86.172268.2135551.499581127.45211204167.7966090548780.1240883902751147 LINKS R. H. Hardin, Table of n, a(n) for n = 1..180 FORMULA Empirical for column k: k=1: a(n) = 2*a(n-1) k=2: a(n) = 2*a(n-1) +a(n-2) -a(n-3) -2*a(n-4) +a(n-5) k=3: a(n) = 5*a(n-1) -5*a(n-2) +8*a(n-3) -12*a(n-4) +4*a(n-5) -4*a(n-6) for n>8 k=4: [order 22] for n>24 k=5: [order 62] for n>65 Empirical for row n: n=1: a(n) = a(n-1) n=2: a(n) = 2*a(n-1) +4*a(n-2) -4*a(n-3) -4*a(n-4) n=3: [order 16] for n>17 n=4: [order 43] for n>44 EXAMPLE Some solutions for n=5 k=4 ..0..0..1..1. .0..0..0..0. .0..0..1..1. .0..0..0..1. .0..0..0..1 ..0..0..1..1. .0..0..0..0. .0..0..1..1. .1..0..0..0. .0..0..0..1 ..0..0..1..1. .1..1..0..0. .1..1..1..1. .0..0..0..1. .1..0..0..0 ..1..1..1..1. .0..1..1..1. .1..1..1..1. .0..0..0..1. .0..0..0..1 ..0..1..1..1. .0..1..1..1. .0..1..1..0. .1..0..0..0. .0..0..0..0 CROSSREFS Column 1 is A000079(n-1). Column 2 is A240513(n-2). Row 2 is A302368. Sequence in context: A302367 A303084 A302889 * A121439 A307448 A305350 Adjacent sequences:  A303621 A303622 A303623 * A303625 A303626 A303627 KEYWORD nonn,tabl AUTHOR R. H. Hardin, Apr 27 2018 STATUS approved

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Last modified December 9 00:32 EST 2019. Contains 329871 sequences. (Running on oeis4.)