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 A204794 Number of (n+1) X 3 0..1 arrays with rows and columns of determinants of all 2 X 2 subblocks lexicographically nondecreasing. 1
 47, 240, 1001, 4273, 18550, 81009, 353975, 1547377, 6764879, 29576797, 129315563, 565399369, 2472075383, 10808590261, 47258158979, 206625890401, 903426368975, 3950033937229, 17270659001435, 75512178579577, 330160485651239 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 2 of A204800. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 6*a(n-1) - 5*a(n-2) - 12*a(n-3) + 12*a(n-4) for n > 8. Empirical g.f.: x*(47 - 42*x - 204*x^2 + 31*x^3 + 233*x^4 + 206*x^5 - 65*x^6 - 104*x^7) / ((1 - x)*(1 - 2*x)*(1 - 3*x - 6*x^2)). - Colin Barker, Jun 10 2018 EXAMPLE Some solutions for n=4: 1 1 1 0 0 1 0 1 0 0 1 1 0 1 0 0 1 0 0 1 1 0 0 0 1 0 0 1 1 0 0 1 1 0 0 0 1 0 1 0 0 0 1 1 0 0 0 0 1 1 0 0 1 1 1 1 0 1 0 0 1 1 0 1 1 0 0 1 1 0 0 0 0 0 0 0 0 0 1 0 1 1 1 0 1 1 1 0 0 0 1 0 0 1 0 0 0 0 1 0 1 0 0 1 1 CROSSREFS Cf. A204800. Sequence in context: A102090 A033226 A142946 * A233823 A142084 A140850 Adjacent sequences: A204791 A204792 A204793 * A204795 A204796 A204797 KEYWORD nonn AUTHOR R. H. Hardin, Jan 19 2012 STATUS approved

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Last modified December 6 18:41 EST 2023. Contains 367614 sequences. (Running on oeis4.)