A196907 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,1,2,0,4 for x=0,1,2,3,4

3, 13, 50, 193, 731, 2843, 10970, 42213, 162766, 627709, 2419707, 9327886, 35961933, 138640724, 534481526, 2060527603, 7943732911, 30624562306, 118063389795, 455156544799, 1754713724522, 6764749611412, 26079376227742, 100540878288579

Offset

1,1

Comments

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

Column 3 of A196912

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = 2*a(n-1) +2*a(n-2) +16*a(n-3) +16*a(n-4) +5*a(n-5) -19*a(n-6) -53*a(n-7) -52*a(n-8) +15*a(n-9) +41*a(n-10) +24*a(n-11) -8*a(n-12) -28*a(n-13) -10*a(n-14) +7*a(n-15) +5*a(n-16) +4*a(n-17) -2*a(n-18)

Example

Some solutions for n=4
..0..0..0....0..0..0....0..0..0....1..2..2....0..0..1....1..0..0....0..0..1
..2..2..0....2..2..1....0..0..0....1..2..2....0..0..1....1..0..1....0..0..1
..2..2..0....2..2..1....0..1..0....0..0..0....0..0..0....0..0..1....1..0..0
..0..0..0....0..0..0....0..1..0....0..0..0....0..1..1....1..1..0....1..0..0

Crossrefs

Sequence in context: A113237 A284329 A259338 * A116427 A008827 A026529

Adjacent sequences: A196904 A196905 A196906 * A196908 A196909 A196910

Keyword

nonn

Author

R. H. Hardin Oct 07 2011

Status

approved