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A189620
Number of 5 X n binary arrays without the pattern 0 1 0 diagonally, antidiagonally or horizontally.
1
32, 1024, 10327, 65160, 532565, 6204967, 68121839, 636683482, 5785616468, 56137313726, 563010113815, 5529846867761, 53193183705288, 513158091226513, 5003028394342619, 48867656731556592, 475282571037202342
OFFSET
1,1
COMMENTS
Row 5 of A189617.
FORMULA
Linear recurrence of order 147 (see links). - Robert Israel, Oct 22 2019
EXAMPLE
Some solutions for 5 X 3:
0 0 0 0 0 0 1 0 1 0 0 0 0 1 1 0 1 1 0 0 0
1 0 1 0 1 1 1 1 1 0 0 1 0 0 1 0 0 0 0 0 0
0 0 1 1 1 1 1 1 1 0 0 0 1 0 0 0 0 1 0 0 1
1 1 0 0 0 1 1 0 0 1 0 1 1 0 0 0 0 1 1 0 0
0 0 1 0 0 1 0 0 0 1 1 1 0 0 1 1 0 0 0 1 1
MAPLE
Compatible:= proc(i, j) local Xi, Xj, k;
Xi:= Configs[i]; Xj:= Configs[j];
if Xi[6..10] <> Xj[1..5] then return 0 fi;
if Xi[1]=0 and ((Xi[6]=1 and Xj[6]=0) or (Xi[7]=1 and Xj[8]=0)) then return 0 fi;
if Xi[2]=0 and ((Xi[7]=1 and Xj[7]=0) or (Xi[8]=1 and Xj[9]=0)) then return 0 fi;
if Xi[3]=0 and ((Xi[7]=1 and Xj[6]=0) or (Xi[8]=1 and Xj[8]=0) or (Xi[9]=1 and Xj[10]=0)) then return 0 fi;
if Xi[4]=0 and ((Xi[8]=1 and Xj[7]=0) or (Xi[9]=1 and Xj[9]=0)) then return 0 fi;
if Xi[5]=0 and ((Xi[9]=1 and Xj[8]=0) or (Xi[10]=1 and Xj[10]=0)) then return 0 fi;
1
end proc:
T:= Matrix(1024, 1024, Compatible):
u:= Vector(1024, 1):
Tu[0]:= u:
for nn from 1 to 30 do Tu[nn]:= T . Tu[nn-1] od:
32, seq(u^%T . Tu[n], n=0..30); # Robert Israel, Oct 22 2019
CROSSREFS
Sequence in context: A016745 A189267 A223672 * A189692 A188743 A188995
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 24 2011
STATUS
approved