cp's OEIS Frontend

A221885 Number of nX4 arrays of occupancy after each element stays put or moves to some horizontal, vertical or antidiagonal neighbor, without consecutive moves in the same direction.

%I A221885 #5 Jul 23 2025 02:18:00
%S A221885 13,3223,449069,65039658,9356131846,1347142288446,193944559610138,
%T A221885 27922276785982528,4019968490456852781,578754876292668561410,
%U A221885 83323335396986744374226,11996060075504536682447230
%N A221885 Number of nX4 arrays of occupancy after each element stays put or moves to some horizontal, vertical or antidiagonal neighbor, without consecutive moves in the same direction.
%C A221885 Column 4 of A221886
%e A221885 Some solutions for n=3
%e A221885 ..0..2..0..1....0..2..0..2....0..0..1..1....0..2..0..2....0..3..0..2
%e A221885 ..1..2..2..1....0..0..1..3....1..3..0..1....0..0..0..2....1..0..1..1
%e A221885 ..0..0..2..1....3..0..1..0....1..0..2..2....1..3..1..1....0..1..2..1
%K A221885 nonn
%O A221885 1,1
%A A221885 _R. H. Hardin_ Jan 30 2013