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 A185479 Number of (n+1) X 2 binary arrays with every 2 X 2 subblock determinant equal to some horizontal or vertical neighbor 2 X 2 subblock determinant. 2
 0, 30, 76, 234, 632, 1832, 5182, 14860, 42346, 121016, 345376, 986330, 2815960, 8040658, 22957720, 65550976, 187164486, 534405148, 1525866290, 4356753200, 12439678168, 35518569746, 101414891304, 289566302122, 826788250864 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Column 1 of A185487. LINKS R. H. Hardin, Table of n, a(n) for n = 1..200 FORMULA Empirical: a(n) = 3*a(n-1) + a(n-2) - 5*a(n-3) + 3*a(n-4) - 2*a(n-6) for n>7. Empirical g.f.: 2*x^2*(15 - 7*x - 12*x^2 + 2*x^3 - 4*x^4 - 2*x^5) / (1 - 3*x - x^2 + 5*x^3 - 3*x^4 + 2*x^6). - Colin Barker, Feb 27 2018 EXAMPLE Some solutions for 3 X 2: ..1..1....1..0....1..0....1..1....0..1....0..0....0..1....1..1....1..1....1..0 ..0..0....0..0....1..0....1..1....0..0....0..0....0..0....1..1....0..0....0..0 ..1..1....1..0....0..0....0..0....0..1....0..0....1..1....1..1....1..0....1..1 CROSSREFS Cf. A185487. Sequence in context: A308137 A179321 A039517 * A045560 A159219 A098998 Adjacent sequences:  A185476 A185477 A185478 * A185480 A185481 A185482 KEYWORD nonn AUTHOR R. H. Hardin, Jan 28 2011 STATUS approved

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Last modified December 14 22:42 EST 2019. Contains 329987 sequences. (Running on oeis4.)