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 A181247 Number of n X 4 binary matrices with no 2 X 2 block having four 1's. 1
 16, 216, 3032, 42176, 587920, 8191392, 114142368, 1590466304, 22161786304, 308805072256, 4302929532288, 59957567962112, 835456401197312, 11641356029819392, 162212139560176128, 2260284639281590272 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 4 of A181253. LINKS R. H. Hardin, Table of n, a(n) for n=1..200 FORMULA Empirical: a(n) = 10*a(n-1) + 54*a(n-2) + 16*a(n-3) - 64*a(n-4). Empirical g.f.: 8*x*(2 + 7*x + x^2 - 8*x^3) / (1 - 10*x - 54*x^2 - 16*x^3 + 64*x^4). - Colin Barker, Mar 26 2018 CROSSREFS Cf. A181253. Sequence in context: A269290 A297098 A159739 * A138454 A235758 A086650 Adjacent sequences:  A181244 A181245 A181246 * A181248 A181249 A181250 KEYWORD nonn AUTHOR R. H. Hardin, Oct 10 2010 STATUS approved

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Last modified October 21 18:54 EDT 2019. Contains 328308 sequences. (Running on oeis4.)