A211840 Number of nonnegative integer arrays of length n+7 with new values 0 upwards introduced in order, no three adjacent elements equal, and containing the value n+1

3199, 14862, 62617, 231046, 748964, 2166176, 5684153, 13733643, 30929368, 65577913, 131970633, 253759834, 468794569, 835883075, 1444053107, 2425000145, 3969547605, 6349093720, 9943187617, 15274563246, 23053165162, 34230925666

Offset

1,1

Comments

Row 6 of A211836

Links

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

Formula

Empirical: a(n) = (1/3840)*n^10 + (23/2304)*n^9 + (197/1152)*n^8 + (9899/5760)*n^7 + (14451/1280)*n^6 + (594979/11520)*n^5 + (8279/48)*n^4 + (138637/320)*n^3 + (583243/720)*n^2 + (62003/60)*n + 685

Example

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

Crossrefs

Sequence in context: A069401 A225056 A306197 * A235786 A235781 A235562

Adjacent sequences: A211837 A211838 A211839 * A211841 A211842 A211843

Keyword

nonn

Author

R. H. Hardin Apr 21 2012

Status

approved