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 A221059 Equals one maps: number of n X 3 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal and antidiagonal neighbors in a random 0..3 n X 3 array. 2
 4, 37, 323, 2735, 22683, 185563, 1503659, 12103019, 96951211, 773938571, 6162595115, 48980025803, 388763683179, 3082612373003, 24424875031211, 193423609703243, 1531129131726827, 12116710888585355, 95865381708690731 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 3 of A221062. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 11*a(n-1) - 10*a(n-2) - 104*a(n-3) - 80*a(n-4) - 8*a(n-5) - 32*a(n-6). Empirical g.f.: x*(4 - 7*x - 44*x^2 - 32*x^3 - 4*x^4 - 16*x^5) / (1 - 11*x + 10*x^2 + 104*x^3 + 80*x^4 + 8*x^5 + 32*x^6). - Colin Barker, Mar 13 2018 EXAMPLE Some solutions for n=3: ..1..0..0....0..0..0....0..0..1....1..0..0....1..1..0....0..0..0....1..1..0 ..1..0..0....1..1..0....0..0..1....1..1..0....0..1..1....0..0..0....1..0..0 ..1..1..0....0..1..1....1..1..0....0..0..1....0..0..0....1..0..1....0..1..0 CROSSREFS Cf. A221062. Sequence in context: A201865 A025542 A162649 * A197966 A199690 A133462 Adjacent sequences:  A221056 A221057 A221058 * A221060 A221061 A221062 KEYWORD nonn AUTHOR R. H. Hardin, Dec 31 2012 STATUS approved

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Last modified December 7 19:20 EST 2021. Contains 349585 sequences. (Running on oeis4.)