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 A281696 Number of 4Xn 0..2 arrays with no element equal to more than one of its horizontal, diagonal or antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards. 1
 0, 222, 19326, 402470, 7497214, 126719222, 1847808312, 25489973264, 335106626139, 4243531978116, 52250869377772, 628947105706014, 7431279191300006, 86458169278267534, 992830171072101269 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row 4 of A281693. LINKS R. H. Hardin, Table of n, a(n) for n = 1..109 EXAMPLE Some solutions for n=3 ..0..1..2. .0..0..0. .0..0..1. .0..1..1. .0..1..2. .0..0..1. .0..1..1 ..2..1..0. .1..1..2. .2..1..2. .1..0..0. .0..1..2. .1..0..2. .0..2..2 ..2..0..0. .1..2..1. .1..0..0. .2..2..1. .1..1..0. .2..0..2. .2..1..1 ..1..1..1. .1..2..0. .2..2..2. .1..0..0. .0..0..2. .1..2..1. .0..1..2 CROSSREFS Cf. A281693. Sequence in context: A043499 A251059 A220230 * A280311 A268024 A267931 Adjacent sequences:  A281693 A281694 A281695 * A281697 A281698 A281699 KEYWORD nonn AUTHOR R. H. Hardin, Jan 27 2017 STATUS approved

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Last modified December 6 10:57 EST 2021. Contains 349563 sequences. (Running on oeis4.)