A183342 - OEIS

%I #5 Mar 31 2012 12:35:50

%S 1,1,1,1,2,1,1,3,3,1,1,4,5,4,1,1,6,7,7,6,1,1,9,13,12,13,9,1,1,13,23,

%T 26,26,23,13,1,1,19,37,51,72,51,37,19,1,1,28,63,97,175,175,97,63,28,1,

%U 1,41,109,193,407,513,407,193,109,41,1,1,60,183,380,1005,1397,1397,1005,380

%N T(n,k)=Number of nXk binary arrays with each 1 adjacent to exactly one 1 vertically and one 1 horizontally

%C Equivalent to all 1s connected only in 2X2 blocks

%C Table starts

%C .1..1...1...1....1.....1......1.......1.......1........1.........1..........1

%C .1..2...3...4....6.....9.....13......19......28.......41........60.........88

%C .1..3...5...7...13....23.....37......63.....109......183.......309........527

%C .1..4...7..12...26....51.....97.....193.....380......741......1456.......2860

%C .1..6..13..26...72...175....407....1005....2450.....5893.....14318......34780

%C .1..9..23..51..175...513...1397....4133...12075....34521....100047.....290287

%C .1.13..37..97..407..1397...4531...16029...55471...188735....651517....2246015

%C .1.19..63.193.1005..4133..16029...68662..286079..1170324...4869491...20218182

%C .1.28.109.380.2450.12075..55471..286079.1429824..6989477..34856362..173451524

%C .1.41.183.741.5893.34521.188735.1170324.6989477.40840428.243887497.1451641573

%H R. H. Hardin, <a href="/A183342/b183342.txt">Table of n, a(n) for n = 1..839</a>

%e Some solutions for 6X5

%e ..0..0..0..0..0....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0

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

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

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

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

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

%Y Diagonal is A145857

%Y Column 2 is A000930(n+1)

%Y Column 3 is A003229

%K nonn,tabl

%O 1,5

%A _R. H. Hardin_ Jan 04 2011