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 A280597 Number of n X n 0..1 arrays with no element equal to more than two of its horizontal, vertical and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards. 0
 1, 7, 45, 302, 1648, 7594, 31152, 119656, 446500, 1658080, 6210762, 23592940, 90908854, 354490210, 1394647332, 5520750316 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Diagonal of A280604. LINKS EXAMPLE Some solutions for n=4 ..0..1..1..0. .0..0..0..0. .0..1..1..0. .0..1..1..0. .0..0..0..0 ..1..0..1..0. .1..1..1..0. .0..0..1..1. .1..0..0..1. .1..1..1..1 ..1..0..1..0. .0..0..1..1. .1..0..0..0. .1..1..1..0. .0..0..0..0 ..0..1..0..1. .1..0..0..1. .1..1..1..1. .0..0..0..1. .1..1..1..1 CROSSREFS Cf. A280604. Sequence in context: A062274 A182556 A219020 * A301319 A143835 A103719 Adjacent sequences:  A280594 A280595 A280596 * A280598 A280599 A280600 KEYWORD nonn AUTHOR R. H. Hardin, Jan 06 2017 STATUS approved

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Last modified December 1 09:28 EST 2020. Contains 338833 sequences. (Running on oeis4.)