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 A295270 Number of n X 3 0..1 arrays with each 1 horizontally or vertically adjacent to 0, 1 or 4 1s. 1
 7, 33, 164, 811, 4035, 19997, 99245, 492401, 2443097, 12121712, 60143345, 298407987, 1480586061, 7346099129, 36448521869, 180843564461, 897276298340, 4451940313371, 22088817679653, 109596228179271, 543774384192739 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 3 of A295275. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 Robert Israel, Maple-assisted proof of formula FORMULA Empirical: a(n) = 2*a(n-1) + 10*a(n-2) + 20*a(n-3) + 17*a(n-4) - a(n-5) - 9*a(n-6) - 12*a(n-7) - a(n-8) - a(n-9) + a(n-10). Empirical formula is true: see link. - Robert Israel, Nov 19 2017 EXAMPLE Some solutions for n=7:   0 1 0    1 0 0    0 0 0    1 0 0    0 1 0    0 1 1    0 0 0   1 1 1    0 0 1    0 0 1    0 1 0    1 0 0    1 0 0    1 0 0   0 1 0    0 0 0    0 0 0    1 0 0    0 0 1    1 0 0    0 0 1   1 0 0    1 0 0    1 0 1    1 0 0    0 0 1    0 0 0    0 0 0   0 0 1    0 1 0    0 0 0    0 0 0    1 1 0    1 0 0    0 1 0   1 0 0    1 0 0    0 1 0    0 0 0    0 0 0    0 0 1    1 0 0   0 1 1    0 1 1    0 0 0    0 0 0    1 0 1    1 0 0    0 0 0 CROSSREFS Cf. A295275. Sequence in context: A304278 A155603 A282991 * A275860 A054256 A085636 Adjacent sequences:  A295267 A295268 A295269 * A295271 A295272 A295273 KEYWORD nonn AUTHOR R. H. Hardin, Nov 19 2017 STATUS approved

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Last modified August 10 04:38 EDT 2020. Contains 336368 sequences. (Running on oeis4.)