A231106 Number of n X 6 0..3 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero.

0, 68, 1748, 53530, 1608428, 48463174, 1459796386, 43973372728, 1324601869208, 39900761486200, 1201923918350574, 36205352039307450, 1090607729123289700, 32852193168911490342, 989601088617366786966, 29809587127374534704744

Offset

1,2

Comments

Column 6 of A231108.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 27*a(n-1) +107*a(n-2) -371*a(n-3) -619*a(n-4) +1973*a(n-5) -4094*a(n-6) -6823*a(n-7) +13505*a(n-8) +32211*a(n-9) +15873*a(n-10) -10017*a(n-11) -12894*a(n-12) -4544*a(n-13) -777*a(n-14) -244*a(n-15) -32*a(n-16) +16*a(n-17) for n>18.

Example

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

Crossrefs

Cf. A231108.

Sequence in context: A329444 A230687 A337962 * A228332 A220722 A017784

Adjacent sequences: A231103 A231104 A231105 * A231107 A231108 A231109

Keyword

nonn

Author

R. H. Hardin, Nov 03 2013

Status

approved