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 A206391 Number of n X 3 0..5 arrays with no element equal to another within a city block distance of two, and new values 0..5 introduced in row major order. 1
 1, 4, 26, 206, 1592, 12428, 96632, 752552, 5856992, 45595664, 354918176, 2762807264, 21506309504, 167411006144, 1303169775488, 10144214859392, 78965192918528, 614685592164608, 4784872150020608, 37246687385693696 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Column 3 of A206396. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 6*a(n-1) + 18*a(n-2) - 32*a(n-3) for n>5. Empirical g.f.: x*(1 - 2*x - 16*x^2 + 10*x^3 + 16*x^4) / (1 - 6*x - 18*x^2 + 32*x^3). - Colin Barker, Jun 16 2018 EXAMPLE Some solutions for n=4: 0 1 2 0 1 2 0 1 2 0 1 2 0 1 2 0 1 2 0 1 2 3 4 5 3 4 5 2 3 4 2 3 0 2 3 4 3 4 5 2 3 0 5 0 1 1 0 3 4 5 1 4 5 1 1 5 0 1 0 3 1 4 5 4 3 2 2 5 1 3 2 0 0 2 4 4 2 3 4 5 1 5 0 1 CROSSREFS Cf. A206396. Sequence in context: A118971 A124554 A321586 * A228966 A291533 A363363 Adjacent sequences: A206388 A206389 A206390 * A206392 A206393 A206394 KEYWORD nonn AUTHOR R. H. Hardin, Feb 07 2012 STATUS approved

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Last modified December 4 14:48 EST 2023. Contains 367563 sequences. (Running on oeis4.)