cp's OEIS Frontend

A231694 Number of nX2 0..3 arrays with no element less than a strict majority of its horizontal, vertical and antidiagonal neighbors.

%I A231694 #7 Jul 23 2025 06:37:30
%S A231694 4,28,272,1998,13260,94996,691229,4926082,35082734,251198534,
%T A231694 1797886622,12852933731,91912956748,657463618650,4702487810918,
%U A231694 33632995941197,240557644773042,1720590474243847,12306454228470804,88021459865552231
%N A231694 Number of nX2 0..3 arrays with no element less than a strict majority of its horizontal, vertical and antidiagonal neighbors.
%C A231694 Column 2 of A231700
%H A231694 R. H. Hardin, <a href="/A231694/b231694.txt">Table of n, a(n) for n = 1..210</a>
%F A231694 Empirical: a(n) = 16*a(n-1) -100*a(n-2) +414*a(n-3) -1560*a(n-4) +4300*a(n-5) -7915*a(n-6) +14336*a(n-7) -26218*a(n-8) +36856*a(n-9) -47376*a(n-10) +63903*a(n-11) -72545*a(n-12) +70297*a(n-13) -69546*a(n-14) +62746*a(n-15) -45905*a(n-16) +31530*a(n-17) -23245*a(n-18) +11184*a(n-19) -5796*a(n-20) +2196*a(n-21) -1296*a(n-22)
%e A231694 Some solutions for n=6
%e A231694 ..3..0....2..2....3..3....0..0....1..1....1..0....2..0....2..2....0..3....1..1
%e A231694 ..0..0....0..0....0..0....0..3....1..3....0..0....0..0....3..2....0..2....1..3
%e A231694 ..2..3....0..3....0..2....0..0....1..2....3..0....1..2....3..2....0..2....2..3
%e A231694 ..0..0....3..0....2..3....0..2....1..0....3..0....0..0....0..0....0..0....0..0
%e A231694 ..0..0....0..0....3..0....1..2....0..0....1..0....0..0....0..0....0..0....0..1
%e A231694 ..2..0....2..1....0..0....1..1....2..1....1..0....0..0....3..2....2..3....3..2
%K A231694 nonn
%O A231694 1,1
%A A231694 _R. H. Hardin_, Nov 12 2013