A254830 Number of length 3 1..(n+1) arrays with every leading partial sum divisible by 2, 3 or 5

4, 13, 30, 54, 95, 121, 185, 259, 376, 450, 643, 750, 992, 1249, 1580, 1768, 2232, 2462, 2998, 3501, 4117, 4459, 5276, 5975, 6855, 7676, 8696, 9261, 10648, 11273, 12617, 13921, 15437, 16899, 18790, 19699, 21588, 23355, 25521, 26644, 29216, 30450, 33004

Offset

1,1

Comments

Row 3 of A254827

Links

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

Formula

Empirical: a(n) = a(n-1) +3*a(n-30) -3*a(n-31) -3*a(n-60) +3*a(n-61) +a(n-90) -a(n-91)

Example

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

Crossrefs

Sequence in context: A161742 A041301 A138989 * A071400 A206806 A022913

Adjacent sequences: A254827 A254828 A254829 * A254831 A254832 A254833

Keyword

nonn

Author

R. H. Hardin, Feb 08 2015

Status

approved