# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a206354 Showing 1-1 of 1 %I A206354 #9 Jun 15 2018 12:00:04 %S A206354 1,17,230,3284,47060,674564,9669452,138605744,1986829652,28480003748, %T A206354 408243662612,5851926480128,83883833763260,1202424123191348, %U A206354 17236024000927580,247068000076467824,3541570646368426820 %N A206354 Number of n X 3 0..4 arrays with no element equal to another within two positions in the same row or column, and new values 0..4 introduced in row major order. %C A206354 Column 3 of A206359. %H A206354 R. H. Hardin, Table of n, a(n) for n = 1..210 %F A206354 Empirical: a(n) = 16*a(n-1) - 20*a(n-2) - 58*a(n-3) + 33*a(n-4) + 30*a(n-5) for n>6. %F A206354 Empirical g.f.: x*(1 + x - 22*x^2 + 2*x^3 + 69*x^4 + 33*x^5) / ((1 - x)*(1 - 15*x + 5*x^2 + 63*x^3 + 30*x^4)). - _Colin Barker_, Jun 15 2018 %e A206354 Some solutions for n=4: %e A206354 ..0..1..2....0..1..2....0..1..2....0..1..2....0..1..2....0..1..2....0..1..2 %e A206354 ..2..0..1....1..0..3....1..0..3....3..2..4....1..3..4....1..2..3....2..3..1 %e A206354 ..1..2..3....2..3..4....2..4..0....4..3..1....2..4..3....2..0..4....1..4..0 %e A206354 ..3..4..2....3..1..2....4..1..2....2..4..3....3..0..1....3..1..2....3..0..2 %Y A206354 Cf. A206359. %K A206354 nonn %O A206354 1,2 %A A206354 _R. H. Hardin_, Feb 06 2012 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE