A252804 Number of (n+2)X(1+2) 0..4 arrays with every consecutive three elements in every row and column not having exactly two distinct values, and in every diagonal and antidiagonal having exactly two distinct values, and new values 0 upwards introduced in row major order

61, 155, 357, 752, 1808, 4045, 8513, 19432, 42308, 88615, 195983, 419484, 874694, 1895805, 4011411, 8333938, 17813212, 37386641, 77434349, 163852856, 341828544, 706141671, 1482930443, 3079373684, 6347000002, 13250880877, 27415373151

Offset

1,1

Comments

Column 1 of A252811

Links

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

Formula

Empirical: a(n) = 6*a(n-1) -11*a(n-2) +14*a(n-3) -60*a(n-4) +120*a(n-5) -29*a(n-6) -16*a(n-7) -165*a(n-8) -180*a(n-9) +994*a(n-10) -952*a(n-11) +280*a(n-12) for n>14

Example

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

Crossrefs

Sequence in context: A316760 A211333 A252811 * A257746 A062661 A044393

Adjacent sequences: A252801 A252802 A252803 * A252805 A252806 A252807

Keyword

nonn

Author

R. H. Hardin, Dec 22 2014

Status

approved