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 A212938 Number of n X 3 0..2 arrays with no column j greater than or equal to than column j-1 in all rows. 1
 1, 181, 9019, 331489, 10669771, 320396041, 9245913139, 260489615329, 7229878904251, 198760197641401, 5430623746397059, 147781972534146769, 4010919223287633931, 108669462396348197161, 2940820425317878781779 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Column 3 of A212943. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 55*a(n-1) - 936*a(n-2) + 4860*a(n-3). a(n) = 10^n - 2*18^n + 27^n. - Vaclav Kotesovec, May 31 2012 Empirical g.f.: x*(1 + 126*x) / ((1 - 10*x)*(1 - 18*x)*(1 - 27*x)). - Colin Barker, Jul 21 2018 EXAMPLE Some solutions for n=4: ..2..1..2....2..2..0....0..0..0....1..0..1....0..1..1....0..1..2....1..1..1 ..0..2..2....2..1..1....2..1..0....2..0..2....2..2..2....0..1..0....2..1..1 ..2..0..0....1..1..0....0..2..0....0..2..2....1..2..2....0..2..1....1..1..1 ..2..1..0....0..1..2....0..0..2....2..1..0....2..1..0....1..0..0....0..1..0 CROSSREFS Cf. A212943. Sequence in context: A293655 A008379 A262141 * A070250 A226714 A083979 Adjacent sequences: A212935 A212936 A212937 * A212939 A212940 A212941 KEYWORD nonn AUTHOR R. H. Hardin, May 31 2012 STATUS approved

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Last modified December 6 22:36 EST 2023. Contains 367616 sequences. (Running on oeis4.)