A245948 Number of length n+3 0..6 arrays with some pair in every consecutive four terms totalling exactly 6

1435, 7669, 39721, 199141, 1021225, 5208673, 26526337, 135336793, 690045061, 3518298991, 17940920173, 91480646389, 466463146399, 2378531818147, 12128251046821, 61842638080231, 315339231002215, 1607932492222021

Offset

1,1

Comments

Column 6 of A245950

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +8*a(n-2) +2*a(n-3) -39*a(n-4) -139*a(n-5) -175*a(n-6) -179*a(n-7) +980*a(n-8) +1638*a(n-9) -1266*a(n-10) -210*a(n-11) -352*a(n-12) +123*a(n-13) +24*a(n-14) +19*a(n-15) -5*a(n-16)

Example

Some solutions for n=4
..3....4....0....4....0....1....3....4....4....1....0....4....4....3....1....4
..6....5....5....6....2....4....2....5....3....1....1....1....3....6....4....1
..1....4....6....1....4....2....3....1....2....4....0....5....3....5....6....1
..0....1....5....0....5....5....4....5....4....2....6....6....3....1....0....5
..6....4....1....6....6....0....2....6....5....4....2....1....3....0....1....3
..6....5....4....2....0....6....2....2....5....0....4....2....1....0....0....1
..1....2....5....1....4....2....1....4....1....4....1....0....2....6....5....5

Crossrefs

Sequence in context: A169822 A114083 A143475 * A221004 A204862 A227494

Adjacent sequences: A245945 A245946 A245947 * A245949 A245950 A245951

Keyword

nonn

Author

R. H. Hardin, Aug 08 2014

Status

approved