cp's OEIS Frontend

A222276 Number of n X 3 0..5 arrays with no entry increasing mod 6 by 5 rightwards or downwards, starting with upper left zero.

%I A222276 #8 Mar 14 2018 15:13:51
%S A222276 25,2205,194485,17153945,1513010465,133450391205,11770577485085,
%T A222276 1038187247574145,91570083319317865,8076654937439905005,
%U A222276 712376276332499775685,62832938018547611186345,5541984245134992804289265
%N A222276 Number of n X 3 0..5 arrays with no entry increasing mod 6 by 5 rightwards or downwards, starting with upper left zero.
%C A222276 Column 3 of A222281.
%H A222276 R. H. Hardin, <a href="/A222276/b222276.txt">Table of n, a(n) for n = 1..210</a>
%F A222276 Empirical: a(n) = 92*a(n-1) - 335*a(n-2).
%F A222276 Conjectures from _Colin Barker_, Mar 14 2018: (Start)
%F A222276 G.f.: 5*x*(5 - 19*x) / (1 - 92*x + 335*x^2).
%F A222276 a(n) = ((46-sqrt(1781))^n*(-801+19*sqrt(1781)) + (46+sqrt(1781))^n*(801+19*sqrt(1781))) / (134*sqrt(1781)).
%F A222276 (End)
%e A222276 Some solutions for n=3:
%e A222276 ..0..0..2....0..3..0....0..3..5....0..0..3....0..3..4....0..0..0....0..3..0
%e A222276 ..4..0..3....0..1..3....0..1..2....2..3..1....2..5..5....1..2..4....3..4..0
%e A222276 ..2..3..1....2..5..1....2..3..3....4..5..3....3..5..2....3..5..1....0..0..1
%Y A222276 Cf. A222281.
%K A222276 nonn
%O A222276 1,1
%A A222276 _R. H. Hardin_, Feb 14 2013