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Number of (2+1)X(n+1) 0..3 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..3 introduced in row major order
1

%I #4 Nov 09 2013 07:30:55

%S 4,8,38,90,363,1163,4151,16054,57977,238042,932432,3836583,15995213,

%T 66369986,282812398,1194269858,5105324531,21834952869,93482382103,

%U 401775486130,1724671120242,7419913219654,31917553521617,137355079265693

%N Number of (2+1)X(n+1) 0..3 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..3 introduced in row major order

%C Row 2 of A231463

%H R. H. Hardin, <a href="/A231465/b231465.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 7*a(n-1) +15*a(n-2) -167*a(n-3) -164*a(n-4) +2252*a(n-5) +1016*a(n-6) -19092*a(n-7) -3372*a(n-8) +110426*a(n-9) +7229*a(n-10) -476069*a(n-11) -5821*a(n-12) +1579769*a(n-13) -6768*a(n-14) -4121058*a(n-15) -8571*a(n-16) +8605523*a(n-17) +144802*a(n-18) -14603860*a(n-19) -452700*a(n-20) +20417020*a(n-21) +778535*a(n-22) -23687301*a(n-23) -869454*a(n-24) +22835452*a(n-25) +638591*a(n-26) -18237245*a(n-27) -206165*a(n-28) +11922975*a(n-29) -148812*a(n-30) -6238980*a(n-31) +241061*a(n-32) +2535855*a(n-33) -158253*a(n-34) -766935*a(n-35) +61092*a(n-36) +160434*a(n-37) -13203*a(n-38) -20493*a(n-39) +1215*a(n-40) +1215*a(n-41)

%e Some solutions for n=7

%e ..0..0..1..0..1..1..0..0....0..0..1..1..2..2..3..3....0..0..1..1..0..0..0..1

%e ..1..1..0..1..0..0..1..1....0..0..1..1..2..2..3..3....0..1..0..1..1..0..1..0

%e ..1..1..1..0..0..1..1..1....0..1..1..1..2..2..2..3....1..0..1..0..0..1..0..1

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 09 2013