A246733 Number of length n+4 0..4 arrays with no pair in any consecutive five terms totalling exactly 4

424, 1096, 2884, 7612, 19992, 52112, 135776, 354428, 926912, 2426008, 6344712, 16581304, 43323852, 113217276, 295956684, 773719596, 2022600900, 5286817120, 13818445276, 36118847720, 94411371892, 246786721208, 645084592792

Offset

1,1

Comments

Column 4 of A246737

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +a(n-4) +24*a(n-5) +2*a(n-6) +5*a(n-7) +11*a(n-8) -8*a(n-10) -2*a(n-11) +3*a(n-12) +a(n-15) +a(n-16)

Example

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

Crossrefs

Sequence in context: A091293 A114808 A134218 * A202772 A220541 A091292

Adjacent sequences: A246730 A246731 A246732 * A246734 A246735 A246736

Keyword

nonn

Author

R. H. Hardin, Sep 02 2014

Status

approved