A196809 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 4,2,3,0,1 for x=0,1,2,3,4.

1, 1, 1, 1, 1, 1, 1, 3, 3, 1, 1, 7, 16, 7, 1, 1, 17, 37, 37, 17, 1, 1, 41, 120, 193, 120, 41, 1, 1, 99, 420, 1515, 1515, 420, 99, 1, 1, 239, 1468, 8719, 19449, 8719, 1468, 239, 1, 1, 577, 4801, 52291, 166682, 166682, 52291, 4801, 577, 1, 1, 1393, 15885, 334317, 1730105

Offset: 1

Author

R. H. Hardin Oct 06 2011

Keywords

• nonn
• tabl

Comments

Every 0 is next to 0 4's, every 1 is next to 1 2's, every 2 is next to 2 3's, every 3 is next to 3 0's, every 4 is next to 4 1's

Table starts

.1....1.....1........1..........1............1..............1................1

.1....1.....3........7.........17...........41.............99..............239

.1....3....16.......37........120..........420...........1468.............4801

.1....7....37......193.......1515.........8719..........52291...........334317

.1...17...120.....1515......19449.......166682........1730105.........18344433

.1...41...420.....8719.....166682......2535368.......46685074........822353649

.1...99..1468....52291....1730105.....46685074.....1436535356......42144649101

.1..239..4801...334317...18344433....822353649....42144649101....2099296647197

.1..577.15885..2067173..186996068..14219232895..1242942835600..105892691714203

.1.1393.53128.12663609.1929020093.247793610490.36966191677933.5317907954180181

Examples

			Some solutions for n=6 k=4
..0..0..0..0....0..0..0..0....0..3..0..0....0..0..3..0....0..3..0..0
..0..3..0..3....0..3..2..0....3..0..3..0....0..0..0..0....0..0..0..0
..0..2..1..0....3..0..3..0....0..0..3..0....0..0..1..0....3..0..0..0
..0..3..0..0....0..3..0..0....3..0..0..0....0..3..2..1....0..3..0..3
..3..0..0..0....0..2..3..0....0..0..0..0....0..0..3..0....1..2..3..0
..0..3..0..0....0..0..0..0....0..3..0..0....0..3..0..0....0..1..0..0
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..220

Crossrefs

Column 2 is A001333(n-1)