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 A202797 Number of n X 3 binary arrays with every one adjacent to another one horizontally or vertically. 1
 4, 36, 250, 1718, 11988, 83518, 581518, 4049700, 28202318, 196400270, 1367728548, 9524845126, 66330898142, 461927514284, 3216857242006, 22402152254494, 156008298702684, 1086439775514766, 7565952552767646, 52689195775528564 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 3 of A202802. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 7*a(n-1) -3*a(n-2) +19*a(n-3) -3*a(n-4) +25*a(n-5) +24*a(n-6) -22*a(n-7) -16*a(n-8). Empirical g.f.: 2*x*(2 + 4*x + 5*x^2 + 20*x^4 + 7*x^5 - 16*x^6 - 8*x^7) / (1 - 7*x + 3*x^2 - 19*x^3 + 3*x^4 - 25*x^5 - 24*x^6 + 22*x^7 + 16*x^8). - Colin Barker, Jun 01 2018 EXAMPLE Some solutions for n=5: ..0..0..0....0..1..0....0..0..1....0..1..1....0..1..1....0..0..1....0..0..0 ..1..0..0....1..1..1....0..0..1....0..1..0....0..0..1....0..0..1....1..0..0 ..1..0..0....0..0..1....1..0..1....1..0..0....1..1..0....0..1..0....1..1..1 ..0..1..1....0..1..0....1..1..1....1..1..1....0..0..0....0..1..1....1..1..1 ..0..1..0....0..1..1....0..1..0....0..0..1....0..1..1....0..0..1....0..1..0 CROSSREFS Cf. A202802. Sequence in context: A295411 A218516 A119579 * A294832 A075144 A183496 Adjacent sequences:  A202794 A202795 A202796 * A202798 A202799 A202800 KEYWORD nonn AUTHOR R. H. Hardin, Dec 24 2011 STATUS approved

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Last modified December 13 08:08 EST 2019. Contains 329968 sequences. (Running on oeis4.)