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A280180
T(n,k)=Number of nXk 0..1 arrays with no element unequal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
7
0, 1, 1, 0, 2, 0, 3, 12, 12, 3, 3, 41, 60, 41, 3, 9, 103, 279, 279, 103, 9, 15, 263, 1082, 1633, 1082, 263, 15, 31, 656, 3931, 8759, 8759, 3931, 656, 31, 57, 1618, 13720, 43094, 63336, 43094, 13720, 1618, 57, 108, 3931, 46467, 202693, 421214, 421214, 202693, 46467
OFFSET
1,5
COMMENTS
Table starts
...0....1......0........3.........3...........9...........15.............31
...1....2.....12.......41.......103.........263..........656...........1618
...0...12.....60......279......1082........3931........13720..........46467
...3...41....279.....1633......8759.......43094.......202693.........919058
...3..103...1082.....8759.....63336......421214......2665301.......16203600
...9..263...3931....43094....421214.....3755997.....31821879......258976696
..15..656..13720...202693...2665301....31821879....359880117.....3910652938
..31.1618..46467...919058..16203600...258976696...3910652938....56789421603
..57.3931.153650..4057457..95738359..2046791216..41205820599...798794739075
.108.9459.499289.17554353.553426602.15814457993.424186764568.10974204206787
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 3*a(n-1) -5*a(n-3) +3*a(n-5) +a(n-6)
k=2: [order 10] for n>14
k=3: [order 21] for n>28
k=4: [order 45] for n>54
EXAMPLE
Some solutions for n=4 k=4
..0..0..1..0. .0..0..0..0. .0..0..0..1. .0..1..1..1. .0..1..1..1
..0..1..0..0. .0..1..0..0. .0..0..0..0. .0..1..1..1. .1..1..1..1
..1..1..0..1. .0..0..0..0. .1..1..1..1. .0..1..0..0. .1..1..1..0
..1..1..0..0. .1..1..1..1. .1..1..1..1. .1..0..0..0. .1..1..1..1
CROSSREFS
Column 1 is A105423(n-2).
Sequence in context: A368584 A368583 A365547 * A337995 A337994 A135433
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Dec 28 2016
STATUS
approved