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Number of nX4 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,0) and new values introduced in order 0..2.
1

%I #4 Jul 20 2016 18:25:24

%S 14,216,339,1302,6448,32388,164645,844176,4319300,22083548,112975642,

%T 578036947,2957212295,15128798774,77399122215,395975649916,

%U 2025811842566,10364054079218,53022552043867,271263640161978,1387785882638203

%N Number of nX4 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,0) and new values introduced in order 0..2.

%C Column 4 of A275228.

%H R. H. Hardin, <a href="/A275224/b275224.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) -4*a(n-2) +18*a(n-4) -213*a(n-5) +254*a(n-6) -43*a(n-7) +348*a(n-8) +571*a(n-9) -1746*a(n-10) -33*a(n-11) +741*a(n-12) -1412*a(n-13) +2606*a(n-14) -243*a(n-15) -667*a(n-16) +1424*a(n-17) -2763*a(n-18) +1382*a(n-19) -742*a(n-20) +329*a(n-21) +281*a(n-22) -97*a(n-23) +88*a(n-24) -62*a(n-25) -27*a(n-26) -3*a(n-27) +7*a(n-28) -a(n-29) +3*a(n-30) -a(n-31) for n>35

%e Some solutions for n=4

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

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

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

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

%Y Cf. A275228.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jul 20 2016