A246886 Number of length n+4 0..2 arrays with some pair in every consecutive five terms totalling exactly 2

231, 673, 1961, 5711, 16621, 48393, 140893, 410197, 1194243, 3476929, 10122747, 29471409, 85803183, 249807769, 727291431, 2117439451, 6164722475, 17947999987, 52253885667, 152132191293, 442918327175, 1289514355131, 3754297734035

Offset

1,1

Comments

Column 2 of A246892

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +2*a(n-2) +a(n-3) +3*a(n-4) -2*a(n-6) -2*a(n-7) -3*a(n-8) -3*a(n-9) +a(n-11) +a(n-13) +a(n-14)

Example

Some solutions for n=6
..1....1....1....2....0....0....1....2....0....0....1....2....2....1....1....0
..2....1....2....2....0....1....1....2....2....0....1....1....0....0....0....1
..2....1....1....1....0....0....2....0....1....2....2....2....1....2....1....1
..0....1....2....1....2....0....2....0....2....1....2....2....0....1....1....2
..0....2....1....2....0....2....0....1....2....1....1....1....0....2....0....0
..0....1....2....2....0....1....1....2....0....1....1....1....1....1....0....2
..1....2....0....2....2....0....0....2....2....0....2....0....1....2....2....0
..2....1....2....0....1....2....1....0....0....2....0....0....0....2....1....2
..0....0....2....1....0....0....1....2....2....1....0....1....0....1....1....0
..1....1....1....0....0....1....2....1....2....1....2....1....0....1....1....2

Crossrefs

Sequence in context: A276832 A324319 A360214 * A258167 A287472 A350368

Adjacent sequences: A246883 A246884 A246885 * A246887 A246888 A246889

Keyword

nonn

Author

R. H. Hardin, Sep 06 2014

Status

approved