A203050 - OEIS

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A203050

Number of nX1 0..5 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor

1, 6, 36, 161, 636, 2507, 10213, 42182, 173606, 710976, 2908797, 11911516, 48807427, 199987737, 819315100, 3356387171, 13749952752, 56330082115, 230771042950, 945410224602, 3873094298871, 15867039092263, 65003096433432

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

OFFSET

1,2

COMMENTS

Column 1 of A203057

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) -15*a(n-2) +35*a(n-3) -35*a(n-4) +56*a(n-5) -28*a(n-6) +36*a(n-7) -9*a(n-8) +10*a(n-9) -a(n-10) +a(n-11)

EXAMPLE

Some solutions for n=5

..3....4....4....3....3....1....3....5....5....4....0....2....4....2....5....2