cp's OEIS Frontend

A189429 Number of n X 3 array permutations with each element not moving, or moving one space N, SW or SE.

%I A189429 #8 May 02 2018 09:23:08
%S A189429 1,3,9,31,109,367,1245,4247,14453,49167,167325,569447,1937829,6594495,
%T A189429 22441517,76369751,259890293,884421039,3009733885,10242290119,
%U A189429 34855077573,118613751711,403649138125,1373640273207,4674573594645
%N A189429 Number of n X 3 array permutations with each element not moving, or moving one space N, SW or SE.
%C A189429 Column 3 of A189435.
%H A189429 R. H. Hardin, <a href="/A189429/b189429.txt">Table of n, a(n) for n = 1..200</a>
%F A189429 Empirical: a(n) = a(n-1) +4*a(n-2) +10*a(n-3) +12*a(n-4) +8*a(n-5).
%F A189429 Empirical g.f.: x*(1 + 2*x + 2*x^2) / (1 - x - 4*x^2 - 10*x^3 - 12*x^4 - 8*x^5). - _Colin Barker_, May 02 2018
%e A189429 Some solutions for 4 X 3:
%e A189429 ..0..4..5....0..4..5....0..1..2....3..1..2....0..4..2....0..4..5....0..1..2
%e A189429 ..6..2..1....1..2..8....3..7..5....6..0..5....1..7..5....3..2..1....3..4..5
%e A189429 ..9..3..8....6..3.11....6.10..4....4.10.11....6..3..8....6..7..8....9.10..8
%e A189429 ..7.10.11....9.10..7....9..8.11....9..8..7....9.10.11....9.10.11....7..6.11
%Y A189429 Cf. A189435.
%K A189429 nonn
%O A189429 1,2
%A A189429 _R. H. Hardin_, Apr 22 2011