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A297314
T(n,k)=Number of nXk 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 or 2 neighboring 1s.
13
1, 2, 1, 4, 7, 1, 7, 23, 21, 1, 12, 66, 117, 65, 1, 21, 207, 497, 609, 200, 1, 37, 654, 2577, 3808, 3159, 616, 1, 65, 2049, 13937, 35476, 29212, 16389, 1897, 1, 114, 6422, 72541, 340825, 484808, 223995, 85041, 5842, 1, 200, 20119, 375054, 2997197, 8273245
OFFSET
1,2
COMMENTS
Table starts
.1.....2.......4.........7..........12............21..............37
.1.....7......23........66.........207...........654............2049
.1....21.....117.......497........2577.........13937...........72541
.1....65.....609......3808.......35476........340825.........2997197
.1...200....3159.....29212......484808.......8273245.......121339476
.1...616...16389....223995.....6623719.....200646607......4893232934
.1..1897...85041...1717882....90535227....4869858862....197589351469
.1..5842..441225..13174266..1237278512..118156684121...7976248015498
.1.17991.2289339.101033369.16909630099.2867120332406.322003901582689
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = 2*a(n-1) +3*a(n-2) +a(n-3)
k=3: a(n) = 3*a(n-1) +11*a(n-2) +3*a(n-3) -6*a(n-4)
k=4: [order 8] for n>9
k=5: [order 12] for n>14
k=6: [order 22] for n>25
k=7: [order 35] for n>39
Empirical for row n:
n=1: a(n) = 2*a(n-1) -a(n-2) +a(n-3)
n=2: [order 9]
n=3: [order 23]
n=4: [order 61]
EXAMPLE
Some solutions for n=5 k=4
..0..1..1..1. .1..1..0..0. .1..1..1..0. .0..1..0..0. .0..0..1..0
..1..0..0..0. .0..0..0..1. .0..0..1..0. .1..1..1..1. .1..1..0..0
..0..1..0..1. .0..0..1..0. .0..1..1..0. .0..0..0..1. .0..0..0..1
..1..1..1..0. .0..0..1..0. .0..1..0..0. .0..0..1..1. .0..1..1..0
..0..0..0..0. .0..1..1..1. .0..1..1..1. .0..0..1..1. .1..0..1..1
CROSSREFS
Column 2 is A218836.
Row 1 is A005251(n+2).
Sequence in context: A193591 A218842 A219421 * A220386 A219410 A221035
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Dec 28 2017
STATUS
approved