Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #4 Dec 21 2012 20:03:20
%S 2,2,2,8,16,8,16,48,48,16,24,256,512,256,24,64,928,4096,4096,928,64,
%T 128,4096,30766,62648,30766,4096,128,232,15820,262144,1048576,1048576,
%U 262144,15820,232,512,65536,2097152,16777216,33358976,16777216,2097152,65536
%N T(n,k)=Sum of neighbor maps: number of nXk binary arrays indicating the locations of corresponding elements equal to the sum mod 4 of their horizontal and vertical neighbors in a random 0..3 nXk array
%C Table starts
%C ....2......2........8........16.........24.........64.........128........232
%C ....2.....16.......48.......256........928.......4096.......15820......65536
%C ....8.....48......512......4096......30766.....262144.....2097152...16728064
%C ...16....256.....4096.....62648....1048576...16777216...268435456.4294967296
%C ...24....928....30766...1048576...33358976.1073741824.34348186888
%C ...64...4096...262144..16777216.1073741824
%C ..128..15820..2097152.268435456
%C ..232..65536.16728064
%C ..512.259584
%C .1024
%H R. H. Hardin, <a href="/A220805/b220805.txt">Table of n, a(n) for n = 1..60</a>
%e Some solutions for n=3 k=4
%e ..0..1..0..0....1..1..1..0....0..1..0..1....1..0..1..0....1..1..0..1
%e ..1..0..0..1....1..0..0..0....0..1..0..0....1..0..1..1....1..0..1..1
%e ..1..0..0..0....1..0..1..1....0..1..1..1....1..0..1..0....1..0..1..0
%Y Column 1 is A220172
%K nonn,tabl
%O 1,1
%A _R. H. Hardin_ Dec 21 2012