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A185903 T(n,k)=1/8 the number of nXk 0..7 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors 4

%I #4 Mar 31 2012 12:36:04

%S 0,1,1,1,15,1,8,196,196,8,15,2765,7854,2765,15,71,38731,546280,546280,

%T 38731,71,176,545328,28967421,139230658,28967421,545328,176,673,

%U 7675381,1748982326,32611077940,32611077940,1748982326,7675381,673,1905

%N T(n,k)=1/8 the number of nXk 0..7 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors

%C Table starts

%C ....0.........1...........1.............8.............15............71

%C ....1........15.........196..........2765..........38731........545328

%C ....1.......196........7854........546280.......28967421....1748982326

%C ....8......2765......546280.....139230658....32611077940.7921723799549

%C ...15.....38731....28967421...32611077940.30884279980274

%C ...71....545328..1748982326.7921723799549

%C ..176...7675381.98953708266

%C ..673.108065699

%C .1905

%e Some solutions for 4X3 with a(1,1)=0

%e ..0..4..5....0..0..4....0..4..0....0..0..6....0..4..2....0..4..6....0..0..3

%e ..0..4..5....4..4..4....0..4..0....4..4..6....0..4..2....0..4..6....4..0..3

%e ..1..1..4....6..7..3....6..6..0....4..4..5....5..3..3....2..0..0....4..0..0

%e ..1..1..4....6..7..3....5..5..0....3..3..5....5..5..5....2..5..5....4..4..4

%Y Column 1 is A015442(n-1)

%K nonn,tabl

%O 1,5

%A _R. H. Hardin_ Feb 06 2011

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Last modified June 11 14:17 EDT 2024. Contains 373311 sequences. (Running on oeis4.)