A204480 Number of (n+2)X7 0..3 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly three ways, and new values 0..3 introduced in row major order

7191, 8114, 2632, 3270, 6494, 11338, 35990, 132258, 473380, 1786812, 6773680, 25609458, 97080840, 368071380, 1395260888, 5289809914, 20055230346, 76034546154, 288268775378, 1092910015022, 4143534627852, 15709332220768

Offset

1,1

Comments

Column 5 of A204483

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +a(n-2) -2*a(n-3) -19*a(n-4) -4*a(n-5) +21*a(n-6) +24*a(n-7) +3*a(n-8) -18*a(n-9) -9*a(n-10) for n>13

Example

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

Crossrefs

Sequence in context: A143193 A064979 A348807 * A035906 A190114 A239566

Adjacent sequences: A204477 A204478 A204479 * A204481 A204482 A204483

Keyword

nonn

Author

R. H. Hardin Jan 15 2012

Status

approved