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Number of nX3 0..2 arrays with no element equal to more than four of its king-move neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
1

%I #4 Feb 08 2017 07:48:14

%S 0,1,44,2919,122866,4446172,148868304,4745726158,146320129628,

%T 4402897631148,130046855804440,3785044372543552,108853806605395072,

%U 3099517720850200120,87515890176533294512,2453231879787924868752

%N Number of nX3 0..2 arrays with no element equal to more than four of its king-move neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

%C Column 3 of A282189.

%H R. H. Hardin, <a href="/A282186/b282186.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 66*a(n-1) -1206*a(n-2) -98*a(n-3) +91188*a(n-4) +644760*a(n-5) -13676*a(n-6) -18240000*a(n-7) -85727400*a(n-8) -8070328*a(n-9) +1357158816*a(n-10) +5154540288*a(n-11) +1290662368*a(n-12) -49451487744*a(n-13) -162002765184*a(n-14) -69484923264*a(n-15) +914711301120*a(n-16) +2709412494336*a(n-17) +1765040047616*a(n-18) -7617338824704*a(n-19) -22456039010304*a(n-20) -22101688217600*a(n-21) +12644626710528*a(n-22) +69535600017408*a(n-23) +105600502628352*a(n-24) +95452790390784*a(n-25) +55231541673984*a(n-26) +20060850880512*a(n-27) +3837602562048*a(n-28) +351629475840*a(n-29) +12230590464*a(n-30) for n>33

%e Some solutions for n=4

%e ..0..0..1. .0..1..1. .0..0..0. .0..0..0. .0..1..0. .0..0..1. .0..0..1

%e ..1..1..1. .2..1..1. .0..0..0. .0..0..0. .2..1..0. .0..0..0. .0..0..0

%e ..1..1..0. .1..1..0. .1..0..1. .1..2..2. .1..1..1. .2..0..0. .1..0..1

%e ..0..0..1. .1..1..0. .1..0..1. .2..2..0. .1..1..1. .0..2..1. .0..2..0

%Y Cf. A282189.

%K nonn

%O 1,3

%A _R. H. Hardin_, Feb 08 2017