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A196989
T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 2,3,4,1,0 for x=0,1,2,3,4
7
1, 1, 1, 1, 1, 1, 1, 3, 3, 1, 1, 5, 10, 5, 1, 1, 9, 25, 25, 9, 1, 1, 17, 81, 113, 81, 17, 1, 1, 31, 242, 547, 547, 242, 31, 1, 1, 57, 707, 2499, 4244, 2499, 707, 57, 1, 1, 105, 2095, 11647, 31791, 31791, 11647, 2095, 105, 1, 1, 193, 6224, 54845, 242602, 389518, 242602
OFFSET
1,8
COMMENTS
Every 0 is next to 0 2's, every 1 is next to 1 3's, every 2 is next to 2 4's, every 3 is next to 3 1's, every 4 is next to 4 0's
Table starts
.1...1.....1.......1.........1..........1............1..............1
.1...1.....3.......5.........9.........17...........31.............57
.1...3....10......25........81........242..........707...........2095
.1...5....25.....113.......547.......2499........11647..........54845
.1...9....81.....547......4244......31791.......242602........1838579
.1..17...242....2499.....31791.....389518......4743311.......58038517
.1..31...707...11647....242602....4743311.....93411402.....1863379223
.1..57..2095...54845...1838579...58038517...1863379223....60168452277
.1.105..6224..256395..13941719..713190410..37097158961..1938441718877
.1.193.18499.1198317.105949190.8761030047.737372275936.62562309931101
LINKS
EXAMPLE
Some solutions for n=6 k=4
..0..1..3..1....1..3..1..0....0..0..0..1....0..0..1..0....0..1..0..0
..0..0..1..0....1..1..0..0....0..0..1..3....0..1..3..0....0..3..1..1
..0..0..0..0....3..1..0..1....0..0..0..1....0..0..1..0....0..1..1..3
..0..1..3..1....1..0..1..3....0..0..4..0....1..0..0..0....0..1..0..1
..0..0..1..0....1..3..1..1....0..4..0..0....3..1..0..0....0..3..1..0
..0..0..0..0....0..1..0..0....0..0..0..0....1..0..0..0....0..1..0..0
CROSSREFS
Column 2 is A000213
Sequence in context: A132729 A196493 A251634 * A034871 A333758 A015109
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Oct 08 2011
STATUS
approved