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 A275499 Number of n X 3 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,0) or (-1,-1) and new values introduced in order 0..2. 1
 5, 54, 80, 136, 232, 516, 1168, 2660, 6024, 13716, 31168, 70868, 161176, 366452, 833360, 1894996, 4309160, 9799012, 22282576, 50670228, 115222840, 262014052, 595814224, 1354867540, 3080938312, 7005983220, 15931445856, 36227745252 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 2*a(n-1) + 2*a(n-2) - 2*a(n-3) - 4*a(n-4) + 3*a(n-5) + a(n-6) - a(n-7) for n>11. Empirical g.f.: x*(5 + 44*x - 38*x^2 - 122*x^3 - 72*x^4 + 141*x^5 + 97*x^6 + 11*x^7 - 106*x^8 - 4*x^9 + 36*x^10) / ((1 - x)*(1 - x - 3*x^2 - x^3 + 3*x^4 - x^6)). - Colin Barker, Feb 04 2019 EXAMPLE Some solutions for n=4: ..0..1..2. .0..0..0. .0..0..1. .0..0..0. .0..1..0. .0..1..0. .0..0..0 ..1..2..2. .1..2..1. .2..1..1. .0..1..2. .1..1..2. .0..1..2. .1..2..2 ..1..2..0. .2..2..1. .2..1..2. .1..2..2. .1..2..2. .1..2..2. .1..2..1 ..2..0..0. .0..0..0. .1..0..2. .1..2..0. .0..0..0. .2..2..0. .0..0..1 CROSSREFS Column 3 of A275504. Sequence in context: A083757 A093674 A129664 * A275396 A275261 A208429 Adjacent sequences:  A275496 A275497 A275498 * A275500 A275501 A275502 KEYWORD nonn AUTHOR R. H. Hardin, Jul 30 2016 STATUS approved

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Last modified December 7 13:08 EST 2021. Contains 349581 sequences. (Running on oeis4.)