A215180 - OEIS

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A215180

Number of nXnXn triangular 0..6 arrays with every horizontal row nondecreasing, first elements of rows nonincreasing, last elements of rows nondecreasing, and every row having the same average value

7, 16, 64, 445, 5096, 102958, 3332921, 183217251, 16238192913, 2328105483906, 511060202579902, 169341739247620227, 80428858087487593154, 54077603387869534941302, 49623033352634628707163403

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Column 6 of A215182

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..67

EXAMPLE

Some solutions for n=4

.....2........3........4........2........4........4........5........4

....2.2......2.4......2.6......2.2......2.6......4.4......5.5......3.5

...1.1.4....1.3.5....1.5.6....2.2.2....1.5.6....2.5.5....3.6.6....3.3.6