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 A228477 Number of nX3 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally. 1
 2, 4, 14, 41, 127, 386, 1181, 3605, 11013, 33635, 102734, 313780, 958385, 2927208, 8940618, 27307464, 83405606, 254747013, 778077691, 2376494562, 7258563605, 22169941573, 67713990833, 206819875427, 631693101322, 1929389878184 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 3 of A228482 Same recurrences as A228285 except in addition a smaller one for column 5 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA a(n) = a(n-1) +5*a(n-2) +4*a(n-3) -a(n-5). G.f.: -x*(-2-2*x+x^3) / ( (1+x)*(x^4-x^3-3*x^2-2*x+1) ). - R. J. Mathar, Aug 25 2013 EXAMPLE Some solutions for n=4 ..1..0..1....1..0..1....1..0..0....1..0..0....1..0..0....1..0..0....1..0..0 ..0..0..0....0..0..0....0..1..0....0..0..1....0..0..0....0..0..0....0..0..1 ..1..0..1....0..0..0....0..0..0....1..0..0....1..0..1....0..0..0....1..0..0 ..0..0..0....0..0..0....1..0..0....0..0..0....0..0..0....0..0..0....0..0..1 CROSSREFS Sequence in context: A279322 A152011 A000912 * A169982 A243323 A128750 Adjacent sequences:  A228474 A228475 A228476 * A228478 A228479 A228480 KEYWORD nonn AUTHOR R. H. Hardin Aug 22 2013 STATUS approved

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Last modified October 16 20:35 EDT 2019. Contains 328103 sequences. (Running on oeis4.)