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A259742
T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00010101 or 01010101
9
20, 22, 22, 42, 36, 42, 62, 74, 74, 62, 101, 136, 190, 136, 101, 152, 230, 374, 374, 230, 152, 265, 414, 792, 868, 792, 414, 265, 382, 760, 1514, 1882, 1882, 1514, 760, 382, 652, 1356, 3480, 4456, 4904, 4456, 3480, 1356, 652, 962, 2414, 6542, 10570, 12086, 12086
OFFSET
1,1
COMMENTS
Table starts
..20...22....42.....62....101.....152......265......382.......652........962
..22...36....74....136....230.....414......760.....1356......2414.......4348
..42...74...190....374....792....1514.....3480.....6542.....14580......27866
..62..136...374....868...1882....4456....10570....24150.....55686.....130032
.101..230...792...1882...4904...12086....35036....82492....230779.....558772
.152..414..1514...4456..12086...36522...110886...321402....940024....2797222
.265..760..3480..10570..35036..110886...416107..1244504...4489732...13887332
.382.1356..6542..24150..82492..321402..1244504..4569918..17054488...64800792
.652.2414.14580..55686.230779..940024..4489732.17054488..77901650..308237826
.962.4348.27866.130032.558772.2797222.13887332.64800792.308237826.1497446190
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-2) +3*a(n-4) +2*a(n-6) for n>7
k=2: a(n) = a(n-1) +2*a(n-3) +a(n-4)
k=3: a(n) = 2*a(n-2) +9*a(n-4) +4*a(n-6) -6*a(n-8) +4*a(n-10) for n>11
k=4: [order 10] for n>11
k=5: [order 18] for n>19
k=6: [order 20] for n>22
k=7: [order 34] for n>37
EXAMPLE
Some solutions for n=4 k=4
..1..0..1..0..1..0....0..1..0..1..0..0....0..0..0..1..0..0....1..0..1..0..1..0
..0..1..0..1..0..1....0..0..1..0..1..0....1..0..1..0..1..0....0..1..0..1..0..0
..1..0..1..0..1..0....0..1..0..1..0..1....0..1..0..1..0..1....1..0..1..0..1..0
..0..1..0..0..0..1....1..0..1..0..1..0....1..0..1..0..1..0....0..1..0..1..0..1
..1..0..1..0..1..0....0..1..0..1..0..0....0..0..0..1..0..1....1..0..0..0..1..0
..0..1..0..1..0..1....0..0..1..0..1..0....0..0..1..0..0..0....0..1..0..1..0..1
CROSSREFS
Sequence in context: A041838 A128356 A109212 * A050653 A267510 A095453
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Jul 04 2015
STATUS
approved