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 A240630 Number of n X n 0..1 arrays with no element equal to exactly three horizontal or vertical neighbors, with new values 0..1 introduced in row major order 0
 1, 8, 129, 4989, 470170, 109584463, 63213422873, 90394294712339, 320691260884992280, 2823496298905253740496 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Diagonal of A240636 LINKS EXAMPLE Some solutions for n=4 ..0..1..0..0....0..1..1..1....0..1..0..1....0..0..1..1....0..1..0..1 ..0..1..0..1....1..1..0..0....0..1..0..0....1..1..0..1....0..0..0..0 ..0..1..1..0....0..0..1..1....1..0..1..1....0..0..0..0....1..1..0..0 ..1..0..1..1....1..0..1..1....1..1..1..0....1..1..0..0....0..1..1..1 CROSSREFS Sequence in context: A073701 A239756 A295240 * A187609 A241076 A222429 Adjacent sequences:  A240627 A240628 A240629 * A240631 A240632 A240633 KEYWORD nonn AUTHOR R. H. Hardin, Apr 09 2014 STATUS approved

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Last modified December 5 23:36 EST 2019. Contains 329784 sequences. (Running on oeis4.)