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A214354
Number of 4X4X4 triangular 0..n arrays with no element lying outside the (possibly reversed) range delimited by its sw and se neighbors
1
160, 2853, 23554, 127813, 529006, 1807653, 5349708, 14150061, 34190300, 76678305, 161533230, 322614617, 615330522, 1127418361, 1993875448, 3417225641, 5694545880, 9252943437, 14695473146, 22859815485, 34892402886, 52341084797
OFFSET
1,1
COMMENTS
Row 4 of A214352
LINKS
FORMULA
Empirical: a(n) = (109/226800)*n^10 + (1531/90720)*n^9 + (1471/6048)*n^8 + (28627/15120)*n^7 + (47321/5400)*n^6 + (107767/4320)*n^5 + (789913/18144)*n^4 + (127789/2835)*n^3 + (111121/4200)*n^2 + (5083/630)*n + 1
EXAMPLE
Some solutions for n=3
.....2........2........1........2........0........2........2........1
....2.2......3.1......0.3......2.1......0.0......3.2......2.1......1.2
...3.0.2....3.1.2....0.0.3....2.1.2....0.0.0....1.3.0....3.1.3....0.2.2
..3.0.2.1..3.0.2.1..0.0.3.1..3.0.2.2..1.0.0.3..1.3.0.1..3.0.3.1..0.1.3.2
CROSSREFS
Sequence in context: A013444 A013448 A234650 * A188306 A189351 A168527
KEYWORD
nonn
AUTHOR
R. H. Hardin Jul 13 2012
STATUS
approved