cp's OEIS Frontend

A221139 T(n,k) = number of n X k arrays of occupancy after each element moves to some horizontal or vertical neighbor, with no occupancy greater than 2.

%I A221139 #13 Jun 28 2017 00:59:38
%S A221139 0,1,1,2,9,2,4,49,49,4,8,289,656,289,8,16,1681,12544,12544,1681,16,32,
%T A221139 9801,200072,643204,200072,9801,32,64,57121,3485689,31203396,31203396,
%U A221139 3485689,57121,64,128,332929,58132316,1539699121,4235650596,1539699121
%N A221139 T(n,k) = number of n X k arrays of occupancy after each element moves to some horizontal or vertical neighbor, with no occupancy greater than 2.
%C A221139 Table starts
%C A221139 ....0........1............2...............4.................8
%C A221139 ....1........9...........49.............289..............1681
%C A221139 ....2.......49..........656...........12544............200072
%C A221139 ....4......289........12544..........643204..........31203396
%C A221139 ....8.....1681.......200072........31203396........4235650596
%C A221139 ...16.....9801......3485689......1539699121......619901126244
%C A221139 ...32....57121.....58132316.....75512292025....86907967843320
%C A221139 ...64...332929....990486784...3709710975721.12474883501876324
%C A221139 ..128..1940449..16699002692.182118668668225
%C A221139 ..256.11309769.282999528529
%C A221139 ..512.65918161
%C A221139 .1024
%C A221139 Even rows and columns are perfect squares.
%H A221139 R. H. Hardin, <a href="/A221139/b221139.txt">Table of n, a(n) for n = 1..84</a>
%e A221139 Some solutions for n=3, k=4:
%e A221139 ..1..1..1..2....1..1..1..1....1..1..0..2....1..1..2..1....1..1..2..0
%e A221139 ..2..1..0..1....0..0..1..0....2..2..1..1....1..2..0..1....1..1..0..0
%e A221139 ..0..1..2..0....2..2..2..1....0..0..2..0....0..2..0..1....1..2..1..2
%Y A221139 Column 1 is A000079(n-2).
%Y A221139 Column 2 is A090390.
%K A221139 nonn,tabl
%O A221139 1,4
%A A221139 _R. H. Hardin_, Jan 02 2013