A254822 Number of length n 1..(3+1) arrays with every leading partial sum divisible by 2, 3 or 5

3, 10, 30, 79, 197, 496, 1262, 3476, 10400, 30718, 86549, 244255, 709450, 2051001, 5691742, 15102696, 39115080, 102078824, 275987219, 775822274, 2223250672, 6380375677, 18280341752, 52328438849, 148625082422, 414077248266

Offset

1,1

Comments

Column 3 of A254827

Links

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

Formula

Empirical: a(n) = 24*a(n-8) +632*a(n-9) +5234*a(n-10) +21008*a(n-11) +50183*a(n-12) +79287*a(n-13) +87918*a(n-14) +70786*a(n-15) +42120*a(n-16) +18620*a(n-17) +6082*a(n-18) +1447*a(n-19) +246*a(n-20) +29*a(n-21) +2*a(n-22)

Example

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

Crossrefs

Sequence in context: A144007 A026960 A026990 * A027256 A332360 A115515

Adjacent sequences: A254819 A254820 A254821 * A254823 A254824 A254825

Keyword

nonn

Author

R. H. Hardin, Feb 08 2015

Status

approved