A252968 Number of (7+2)X(n+2) 0..4 arrays with every consecutive three elements in every row and diagonal having exactly two distinct values, and in every column and antidiagonal not having exactly two distinct values, and new values 0 upwards introduced in row major order

7637, 2279, 2999, 4275, 6091, 8767, 12573, 19192, 27929, 42791, 65583, 101848, 157361, 254327, 399081, 649951, 1052501, 1735205, 2832701, 4772867, 7869665, 13341100, 22324855, 38106121, 64052857, 110368012, 186366733, 322104251

Offset

1,1

Comments

Row 7 of A252961

Links

R. H. Hardin, Table of n, a(n) for n = 1..100

Formula

Empirical: a(n) = 6*a(n-2) +6*a(n-3) -10*a(n-4) -36*a(n-5) -9*a(n-6) +60*a(n-7) +68*a(n-8) -6*a(n-9) -108*a(n-10) -48*a(n-11) +24*a(n-12) +48*a(n-13) +25*a(n-14) -24*a(n-15) +22*a(n-16) -30*a(n-17) +22*a(n-18) -12*a(n-19) +33*a(n-20) -12*a(n-21) -18*a(n-23) for n>25

Example

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

Crossrefs

Sequence in context: A068245 A189551 A235907 * A252051 A038011 A205040

Adjacent sequences: A252965 A252966 A252967 * A252969 A252970 A252971

Keyword

nonn

Author

R. H. Hardin, Dec 25 2014

Status

approved