A248535 Number of length n+3 0..6 arrays with every four consecutive terms having the sum of some three elements equal to three times the fourth

331, 427, 555, 715, 907, 1219, 1635, 2167, 2827, 3895, 5307, 7111, 9355, 13051, 17931, 24151, 31867, 44815, 61923, 83683, 110587, 156583, 217419, 294643, 389803, 555535, 774963, 1052959, 1394395, 1999867, 2802291, 3817003, 5059339, 7300363, 10273059

Offset

1,1

Comments

Column 6 of A248537

Links

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

Formula

Empirical: a(n) = a(n-1) +8*a(n-4) -8*a(n-5) -19*a(n-8) +19*a(n-9) +13*a(n-12) -13*a(n-13) -4*a(n-16) +4*a(n-17)

Example

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

Crossrefs

Sequence in context: A179400 A139657 A140000 * A142763 A020373 A142601

Adjacent sequences: A248532 A248533 A248534 * A248536 A248537 A248538

Keyword

nonn

Author

R. H. Hardin, Oct 08 2014

Status

approved