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A302889
T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2, 3, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
12
1, 1, 2, 1, 2, 4, 1, 12, 2, 8, 1, 20, 37, 3, 16, 1, 72, 53, 141, 6, 32, 1, 168, 197, 238, 569, 10, 64, 1, 496, 818, 2278, 1102, 2262, 21, 128, 1, 1296, 2548, 12782, 20937, 5570, 8968, 42, 256, 1, 3616, 10926, 98458, 200186, 206332, 28594, 35667, 86, 512, 1, 9760, 42671
OFFSET
1,3
COMMENTS
Table starts
...1..1......1......1.........1...........1.............1...............1
...2..2.....12.....20........72.........168...........496............1296
...4..2.....37.....53.......197.........818..........2548...........10926
...8..3....141....238......2278.......12782.........98458..........714934
..16..6....569...1102.....20937......200186.......2727690........37626360
..32.10...2262...5570....206332.....3452246......89290791......2247650354
..64.21...8968..28594...2059835....60501563....2899297652....133518102376
.128.42..35667.149206..20622709..1073161270...94799190457...7977498513759
.256.86.141839.788373.206851726.19073141368.3098646840396.476377988322833
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-1)
k=2: a(n) = 2*a(n-1) +a(n-2) -a(n-3) -2*a(n-4) +a(n-5)
k=3: [order 10]
k=4: [order 35] for n>37
Empirical for row n:
n=1: a(n) = a(n-1)
n=2: a(n) = 2*a(n-1) +4*a(n-2) -4*a(n-3) -4*a(n-4)
n=3: [order 16] for n>17
n=4: [order 51] for n>54
EXAMPLE
Some solutions for n=5 k=4
..0..1..1..0. .0..1..1..1. .0..1..1..0. .0..0..0..0. .0..1..1..0
..1..1..1..0. .1..1..1..0. .0..1..1..0. .1..0..0..1. .0..1..1..1
..0..1..1..0. .0..1..1..0. .0..1..1..1. .1..0..0..1. .0..1..1..1
..0..1..1..0. .0..1..1..1. .1..1..1..0. .0..0..0..0. .1..1..1..0
..0..1..1..1. .0..1..1..0. .0..1..1..1. .0..0..0..1. .1..1..1..0
CROSSREFS
Column 1 is A000079(n-1).
Column 2 is A240513(n-2).
Row 2 is A302368.
Sequence in context: A303242 A302367 A303084 * A303624 A121439 A307448
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Apr 15 2018
STATUS
approved