cp's OEIS Frontend

A221693 T(n,k)=Number of nXk arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, without consecutive moves in the same direction.

%I A221693 #6 Jul 23 2025 02:07:24
%S A221693 1,3,1,6,21,1,13,152,144,1,28,1336,3112,987,1,60,11036,95076,63676,
%T A221693 6765,1,129,92660,2627760,7033429,1302720,46368,1,277,774380,74531185,
%U A221693 659020617,520770016,26650988,317811,1,595,6479664,2098932856
%N A221693 T(n,k)=Number of nXk arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, without consecutive moves in the same direction.
%C A221693 Table starts
%C A221693 .1.........3............6..............13................28................60
%C A221693 .1........21..........152............1336.............11036.............92660
%C A221693 .1.......144.........3112...........95076...........2627760..........74531185
%C A221693 .1.......987........63676.........7033429.........659020617.......64509677154
%C A221693 .1......6765......1302720.......520770016......164441398718....55433846144035
%C A221693 .1.....46368.....26650988.....38558774282....41023076707062.47681199145323119
%C A221693 .1....317811....545221260...2854945130275.10233875156794211
%C A221693 .1...2178309..11154026300.211383822013331
%C A221693 .1..14930352.228186749552
%C A221693 .1.102334155
%C A221693 .1
%H A221693 R. H. Hardin, <a href="/A221693/b221693.txt">Table of n, a(n) for n = 1..70</a>
%e A221693 Some solutions for n=3 k=4
%e A221693 ..0..3..0..1....0..4..0..1....2..0..2..0....0..3..2..0....2..1..0..1
%e A221693 ..0..1..0..1....1..1..1..1....1..0..0..2....0..1..1..1....0..2..3..0
%e A221693 ..1..2..3..0....1..1..0..1....1..3..0..1....2..0..1..1....1..1..0..1
%Y A221693 Column 2 is A033888
%Y A221693 Row 1 is A002478
%K A221693 nonn,tabl
%O A221693 1,2
%A A221693 _R. H. Hardin_ Jan 22 2013