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 A275567 Number of 4Xn 0..2 arrays with no element equal to any value at offset (-2,0) (-1,2) or (0,-2) and new values introduced in order 0..2. 1
 6, 216, 504, 1176, 3192, 8664, 23712, 64896, 180960, 504600, 1418100, 3985350, 11202990, 31492086, 88441764, 248378136, 697381260, 1958065350, 5498516310, 15440588646, 43363859406, 121784495766, 342029032494, 960580887846 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row 4 of A275565. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 5*a(n-1) -35*a(n-3) +31*a(n-4) +131*a(n-5) -205*a(n-6) -254*a(n-7) +705*a(n-8) -6*a(n-9) -1218*a(n-10) +823*a(n-11) +1150*a(n-12) -1646*a(n-13) -439*a(n-14) +1789*a(n-15) -394*a(n-16) -1015*a(n-17) +499*a(n-18) +285*a(n-19) -205*a(n-20) -46*a(n-21) +51*a(n-22) -6*a(n-24) +a(n-25) for n>28 EXAMPLE Some solutions for n=4 ..0..0..1..1. .0..1..2..2. .0..1..1..0. .0..1..2..0. .0..1..1..0 ..0..0..2..2. .1..0..0..1. .2..1..0..0. .1..1..0..2. .2..1..0..0 ..1..1..0..0. .1..2..0..0. .2..2..0..1. .2..0..1..1. .1..2..0..1 ..2..2..0..1. .2..1..1..0. .1..0..2..1. .2..2..1..0. .1..2..2..1 CROSSREFS Cf. A275565. Sequence in context: A002037 A332989 A030265 * A007221 A195802 A145249 Adjacent sequences:  A275564 A275565 A275566 * A275568 A275569 A275570 KEYWORD nonn AUTHOR R. H. Hardin, Aug 01 2016 STATUS approved

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Last modified October 30 06:31 EDT 2020. Contains 338077 sequences. (Running on oeis4.)