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 A204624 Number of (n+1) X 3 0..2 arrays with every 2 X 2 subblock having unequal diagonal elements or unequal antidiagonal elements, and new values 0..2 introduced in row major order. 1
 96, 2049, 43734, 933462, 19923888, 425257068, 9076721064, 193734264456, 4135079723136, 88259474206608, 1883817316421472, 40208348322379872, 858210220662456576, 18317707978060726464, 390974632428061590144 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 2 of A204630. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 22*a(n-1) -14*a(n-2). Conjectures from Colin Barker, Jun 07 2018: (Start) G.f.: 3*x*(32 - 21*x) / (1 - 22*x + 14*x^2). a(n) = (3*(11+sqrt(107))^n*(31+3*sqrt(107)) + (11-sqrt(107))^n*(-93+9*sqrt(107))) / (4*sqrt(107)). (End) EXAMPLE Some solutions for n=3: ..0..0..0....0..0..1....0..0..1....0..1..2....0..0..1....0..0..1....0..1..0 ..0..1..1....2..0..2....2..0..2....1..2..2....2..0..0....2..0..2....2..1..2 ..1..2..0....0..0..2....2..2..1....0..2..1....2..0..1....1..0..2....2..1..1 ..1..2..1....2..0..2....0..2..1....1..1..0....2..2..2....1..2..1....0..1..2 CROSSREFS Cf. A204630. Sequence in context: A159711 A268636 A233153 * A090449 A336677 A233709 Adjacent sequences: A204621 A204622 A204623 * A204625 A204626 A204627 KEYWORD nonn AUTHOR R. H. Hardin, Jan 17 2012 STATUS approved

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Last modified December 8 08:53 EST 2022. Contains 358693 sequences. (Running on oeis4.)