A246484 Number of length 5+3 0..n arrays with no pair in any consecutive four terms totalling exactly n

2, 38, 1420, 11020, 92478, 415650, 1756472, 5497304, 16089370, 39798430, 93260292, 196688868, 397729430, 748819610, 1364059888, 2360459440, 3978481842, 6452033814, 10241689340, 15777507260, 23878671982, 35285572498, 51371705640

Offset

1,1

Comments

Row 5 of A246479

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +3*a(n-2) -17*a(n-3) +3*a(n-4) +39*a(n-5) -25*a(n-6) -45*a(n-7) +45*a(n-8) +25*a(n-9) -39*a(n-10) -3*a(n-11) +17*a(n-12) -3*a(n-13) -3*a(n-14) +a(n-15)

Example

Some solutions for n=5
..5....1....5....4....1....3....4....1....1....5....3....2....3....2....1....5
..5....1....1....2....0....3....4....2....1....2....1....0....3....1....2....4
..2....3....5....0....1....4....0....5....0....2....3....0....1....2....5....4
..5....3....1....0....2....3....3....5....0....5....0....0....1....0....2....3
..1....3....2....1....2....0....3....2....1....4....1....3....0....1....5....5
..1....4....2....1....2....3....0....2....0....5....0....0....0....1....5....5
..3....0....5....0....1....3....0....4....1....5....2....1....3....3....5....4
..0....4....4....3....5....4....0....4....3....3....0....1....1....1....5....3

Crossrefs

Sequence in context: A291821 A187544 A187545 * A288027 A184994 A334554

Adjacent sequences: A246481 A246482 A246483 * A246485 A246486 A246487

Keyword

nonn

Author

R. H. Hardin, Aug 27 2014

Status

approved