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 A269272 Number of n X 4 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once. 1
 108, 13896, 1104264, 74853576, 4684312584, 279339197256, 16128206816904, 909870855444936, 50443519266217224, 2758864964165996616, 149253876730080113544, 8002845140585293252296, 425920265748436386105864 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 98*a(n-1) - 2401*a(n-2) for n > 3. Conjectures from Colin Barker, Jan 20 2019: (Start) G.f.: 36*x*(3 + 92*x + 49*x^2) / (1 - 49*x)^2. a(n) = 72 * 49^(n-2) * (120*n-47) for n>1. (End) EXAMPLE Some solutions for n=2: 3 2 2 0 1 1 0 0 3 0 2 3 0 2 0 3 2 2 3 2 2 2 3 2 1 3 2 0 2 0 1 0 2 2 2 3 0 2 3 0 CROSSREFS Column 4 of A269276. Sequence in context: A269093 A113853 A209043 * A209015 A299951 A230273 Adjacent sequences: A269269 A269270 A269271 * A269273 A269274 A269275 KEYWORD nonn AUTHOR R. H. Hardin, Feb 21 2016 STATUS approved

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Last modified December 4 11:13 EST 2022. Contains 358556 sequences. (Running on oeis4.)