A206983 Number of nX4 0..1 arrays avoiding the patterns 0 1 0 or 1 0 1 in any row, column, diagonal or antidiagonal

10, 100, 158, 556, 1866, 5804, 18528, 59888, 191484, 612874, 1966402, 6301118, 20187672, 64705162, 207369486, 664535672, 2129687696, 6825166670, 21872797724, 70096742330, 224642588748, 719921959060, 2307166259316, 7393882758084

Offset

1,1

Comments

Column 4 of A206987

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -4*a(n-2) +10*a(n-3) -18*a(n-4) +8*a(n-5) -16*a(n-6) -4*a(n-7) -3*a(n-8) +21*a(n-9) +13*a(n-10) -12*a(n-11) for n>13

Example

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

Crossrefs

Sequence in context: A031187 A029797 A367593 * A207841 A072082 A078259

Adjacent sequences: A206980 A206981 A206982 * A206984 A206985 A206986

Keyword

nonn

Author

R. H. Hardin Feb 14 2012

Status

approved