A238808 Number of n X 4 0..2 arrays with no element equal to one plus the sum of elements to its left or one plus the sum of the sum of elements above it, modulo 3.

5, 25, 118, 468, 1501, 4167, 10423, 24115, 52449, 108395, 214496, 408732, 753333, 1347741, 2347301, 3989727, 6631953, 10800653, 17260510, 27105244, 41877485, 63724811, 95600675, 141520531, 206885249, 298885895, 427006156, 603641124

Offset

1,1

Comments

Column 4 of A238812.

Links

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

Formula

Empirical: a(n) = (1/302400)*n^10 - (13/90720)*n^9 + (37/6720)*n^8 - (451/3780)*n^7 + (29063/14400)*n^6 - (100891/4320)*n^5 + (11871787/60480)*n^4 - (25402589/22680)*n^3 + (35075741/8400)*n^2 - (2861612/315)*n + 8719 for n>4.

Example

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

Crossrefs

Cf. A238812.

Sequence in context: A055297 A244828 A357598 * A034274 A110212 A344097

Adjacent sequences: A238805 A238806 A238807 * A238809 A238810 A238811

Keyword

nonn

Author

R. H. Hardin, Mar 05 2014

Status

approved