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 A251082 Number of (n+1) X (2+1) 0..2 arrays with no 2 X 2 subblock having the sum of its diagonal elements greater than the absolute difference of its antidiagonal elements. 1
 83, 284, 616, 1306, 2534, 4848, 9086, 17102, 32336, 61836, 119420, 232882, 457522, 904088, 1793778, 3569126, 7114892, 14200724, 28365600, 56687594, 113322526, 226582144, 453089606, 906091326, 1812079784, 3624040028, 7247941796 (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) = 6*a(n-1) - 13*a(n-2) + 10*a(n-3) + 5*a(n-4) - 14*a(n-5) + 9*a(n-6) - 2*a(n-7) for n>8. Empirical g.f.: x*(83 - 214*x - 9*x^2 + 472*x^3 - 549*x^4 + 204*x^5 + 29*x^6 - 26*x^7) / ((1 - x)^5*(1 + x)*(1 - 2*x)). - Colin Barker, Nov 24 2018 EXAMPLE Some solutions for n=4: ..0..1..2....2..0..2....0..0..2....0..1..2....0..0..2....0..0..2....0..0..1 ..0..0..1....2..0..2....0..0..2....0..0..0....0..0..2....0..0..1....0..0..1 ..0..0..0....2..0..1....0..0..2....1..1..1....1..0..0....0..0..1....1..0..1 ..0..0..0....2..0..1....0..0..0....0..0..0....1..0..0....0..0..0....1..0..1 ..1..1..0....2..0..1....2..0..0....2..1..0....2..1..1....2..1..1....1..0..0 CROSSREFS Column 2 of A251088. Sequence in context: A142387 A145651 A244776 * A141570 A334644 A288172 Adjacent sequences: A251079 A251080 A251081 * A251083 A251084 A251085 KEYWORD nonn AUTHOR R. H. Hardin, Nov 29 2014 STATUS approved

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Last modified December 5 21:40 EST 2022. Contains 358594 sequences. (Running on oeis4.)