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 A299589 Number of n X n 0..1 arrays with every element unequal to 0, 1 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
 1, 1, 5, 23, 113, 576, 2583, 11656, 54738, 252959, 1159927, 5359097, 24760544, 114126327, 526426848, 2429504050, 11207820807, 51702119063, 238537489057, 1100501704736, 5077031912807, 23422773519432, 108060889914594 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Diagonal of A299595. LINKS R. H. Hardin, Table of n, a(n) for n = 1..70 FORMULA Empirical: a(n) = 3*a(n-1) +2*a(n-2) +28*a(n-3) -2*a(n-4) -42*a(n-5) -56*a(n-6) +50*a(n-7) -44*a(n-8) +30*a(n-9) -44*a(n-10) +2*a(n-11) +2*a(n-12) -a(n-14) +a(n-15) for n>18. EXAMPLE Some solutions for n=5 ..0..0..0..0..0. .0..0..1..0..0. .0..0..1..0..0. .0..0..0..0..0 ..0..0..0..0..0. .0..0..0..0..1. .0..0..0..0..0. .0..0..0..0..0 ..1..0..0..0..1. .0..0..0..0..0. .0..0..0..0..0. .1..0..0..0..0 ..0..0..0..0..0. .1..0..0..0..0. .0..0..0..0..0. .0..0..0..0..1 ..0..1..0..0..0. .0..0..0..1..0. .0..0..0..1..0. .0..1..0..0..0 CROSSREFS Cf. A299595. Sequence in context: A186652 A199312 A320326 * A113284 A104090 A355055 Adjacent sequences:  A299586 A299587 A299588 * A299590 A299591 A299592 KEYWORD nonn AUTHOR R. H. Hardin, Feb 13 2018 STATUS approved

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Last modified August 10 10:09 EDT 2022. Contains 356039 sequences. (Running on oeis4.)