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 A205066 Number of (n+1) X 3 0..1 arrays with the number of rightwards and downwards edge increases in each 2 X 2 subblock differing from the number in all its horizontal and vertical neighbors. 1
 40, 64, 90, 146, 244, 386, 638, 1018, 1666, 2676, 4360, 7024, 11418, 18420, 29882, 48272, 78228, 126456, 204798, 331194, 536146, 867282, 1403624, 2270906, 3674698, 5945848, 9620410, 15567302, 25186452, 40757134, 65938814, 106705842, 172629762 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 2 of A205072. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 3*a(n-2) - a(n-6) - 4*a(n-8) - a(n-10) + a(n-12) for n > 14. Empirical g.f.: 2*x*(20 + 32*x - 15*x^2 - 23*x^3 - 13*x^4 - 26*x^5 - 27*x^6 - 38*x^7 + x^8 + 12*x^9 + 3*x^10 + 15*x^11 + x^12 - 4*x^13) / ((1 + x - x^2)*(1 - x + x^2)*(1 - x - x^2)*(1 + x + x^2)*(1 - x^2 - x^4)). - Colin Barker, Jun 10 2018 EXAMPLE Some solutions for n=4: 1 1 1 1 1 0 0 1 0 1 0 0 1 0 0 1 0 0 1 1 0 1 0 1 0 1 0 1 1 1 0 1 0 0 1 0 0 1 0 1 1 1 1 1 1 1 1 1 0 1 1 0 0 1 0 0 0 0 0 1 0 1 1 0 0 1 0 1 1 1 0 1 0 0 0 0 1 0 0 0 0 1 0 1 1 0 1 1 0 1 1 1 1 1 0 0 0 0 1 1 0 1 1 1 1 CROSSREFS Cf. A205072. Sequence in context: A060672 A204754 A204747 * A232870 A338373 A355778 Adjacent sequences: A205063 A205064 A205065 * A205067 A205068 A205069 KEYWORD nonn AUTHOR R. H. Hardin, Jan 21 2012 STATUS approved

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Last modified June 4 23:50 EDT 2023. Contains 363130 sequences. (Running on oeis4.)