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 A207937 Number of n X 7 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 1 0 vertically. 1
 35, 1225, 8977, 38207, 121313, 319439, 737575, 1544037, 2994871, 5463725, 9477733, 15759955, 25278917, 39305795, 59479787, 87882217, 127119915, 180418417, 251725529, 345825799, 468466441, 626495255, 828011087, 1082527373, 1401149311 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 7 of A207938. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8). Conjectures from Colin Barker, Jun 26 2018: (Start) G.f.: x*(35 + 945*x + 157*x^2 - 1269*x^3 + 863*x^4 - 191*x^5 + 5*x^6 - x^7) / (1 - x)^8. a(n) = (1260 + 4974*n - 32165*n^2 - 6041*n^3 + 51940*n^4 + 21091*n^5 + 2905*n^6 + 136*n^7) / 1260. (End) EXAMPLE Some solutions for n=4: ..1..0..1..0..1..0..1....1..0..1..0..1..1..0....1..1..1..1..1..1..1 ..1..1..0..1..0..1..0....1..1..1..1..0..1..0....0..1..1..1..1..0..1 ..1..0..1..0..1..1..0....1..0..1..0..1..1..0....1..1..1..1..1..1..1 ..1..0..1..1..1..1..0....1..0..1..1..1..1..0....0..1..1..1..1..0..1 CROSSREFS Cf. A207938. Sequence in context: A207568 A209649 A207756 * A208697 A207504 A207965 Adjacent sequences:  A207934 A207935 A207936 * A207938 A207939 A207940 KEYWORD nonn AUTHOR R. H. Hardin, Feb 21 2012 STATUS approved

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Last modified December 6 16:26 EST 2021. Contains 349567 sequences. (Running on oeis4.)