A204885 Number of (n+2)X3 0..2 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally, and new values 0..2 introduced in row major order

1864, 34925, 667323, 12188762, 225832062, 4194241697, 77625757337, 1438033753446, 26646509815472, 493623796285245, 9144880573523055, 169422165807481702, 3138728408835351358, 58148543218721610541

Offset

1,1

Comments

Column 1 of A204889

Links

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

Formula

Empirical: a(n) = 19*a(n-1) -21*a(n-2) +627*a(n-3) -8116*a(n-4) +11020*a(n-5) +28073*a(n-6) +117741*a(n-7) +10119*a(n-8) -840305*a(n-9) -2149820*a(n-10) -1826454*a(n-11) +2639994*a(n-12) +3894640*a(n-13) -6947224*a(n-14) -5854276*a(n-15) +30431520*a(n-16) +11575704*a(n-17) -51437432*a(n-18) -10392032*a(n-19) +36522224*a(n-20) +13287456*a(n-21) -12797984*a(n-22) -15448640*a(n-23) +5774528*a(n-24) +4714240*a(n-25) -371712*a(n-26) -50176*a(n-27) -1627136*a(n-28) +614400*a(n-29) +221184*a(n-30) -92160*a(n-31)

Example

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

Crossrefs

Sequence in context: A237257 A252137 A204889 * A231029 A265456 A023744

Adjacent sequences: A204882 A204883 A204884 * A204886 A204887 A204888

Keyword

nonn

Author

R. H. Hardin Jan 20 2012

Status

approved