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 A228386 Number of n X 4 binary arrays with top left value 1 and no two ones adjacent horizontally or vertically. 1
 3, 12, 72, 382, 2104, 11449, 62546, 341249, 1862631, 10165343, 55480071, 302792766, 1652555713, 9019158650, 49223917246, 268649627276, 1466210540982, 8002145144295, 43673350799304, 238356282199103, 1300878367732021 (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) = 4*a(n-1) +9*a(n-2) -5*a(n-3) -4*a(n-4) +a(n-5). Empirical g.f.: x*(3 - 3*x^2 + x^3) / (1 - 4*x - 9*x^2 + 5*x^3 + 4*x^4 - x^5). - Colin Barker, Sep 11 2018 EXAMPLE Some solutions for n=4: ..1..0..0..0....1..0..1..0....1..0..1..0....1..0..1..0....1..0..1..0 ..0..1..0..0....0..0..0..1....0..1..0..1....0..1..0..1....0..0..0..0 ..1..0..1..0....1..0..1..0....0..0..0..0....1..0..1..0....1..0..1..0 ..0..0..0..0....0..1..0..0....0..1..0..1....0..0..0..0....0..1..0..1 CROSSREFS Column 4 of A228390. Sequence in context: A112320 A103366 A277457 * A175836 A293138 A319948 Adjacent sequences:  A228383 A228384 A228385 * A228387 A228388 A228389 KEYWORD nonn AUTHOR R. H. Hardin, Aug 21 2013 STATUS approved

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Last modified September 16 12:39 EDT 2019. Contains 327112 sequences. (Running on oeis4.)