login

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”).

T(n,k)=Number of nXk 0..3 arrays with no more than floor(nXk/2) elements equal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order
4

%I #4 Mar 06 2013 19:47:14

%S 1,1,1,2,8,2,11,105,105,11,34,1585,4797,1585,34,131,23107,326408,

%T 326408,23107,131,438,353631,15364848,70144361,15364848,353631,438,

%U 2150,5338646,1077545438,15371324917,15371324917,1077545438,5338646,2150,7676

%N T(n,k)=Number of nXk 0..3 arrays with no more than floor(nXk/2) elements equal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order

%C Table starts

%C .....1..........1.............2..............11................34

%C .....1..........8...........105............1585.............23107

%C .....2........105..........4797..........326408..........15364848

%C ....11.......1585........326408........70144361.......15371324917

%C ....34......23107......15364848.....15371324917....10720259944904

%C ...131.....353631....1077545438...3410802057085.11000375151330544

%C ...438....5338646...52487425596.763478480305913

%C ..2150...81874696.3689615795056

%C ..7676.1252153841

%C .32491

%H R. H. Hardin, <a href="/A222842/b222842.txt">Table of n, a(n) for n = 1..60</a>

%e Some solutions for n=3 k=4

%e ..0..1..0..2....0..1..0..1....0..1..0..2....0..1..0..0....0..1..1..2

%e ..3..0..3..2....1..2..1..0....0..0..2..2....2..2..0..1....1..0..2..3

%e ..2..1..3..0....0..1..2..2....2..1..0..3....3..0..1..0....0..1..2..3

%Y Column 1 is A222650

%K nonn,tabl

%O 1,4

%A _R. H. Hardin_ Mar 06 2013