A208170 - OEIS

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A208170

Number of n X 3 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than one of its immediate leftward or upward neighbors.

5, 159, 8469, 473928, 26625693, 1496307201, 84091222866, 4725865313907, 265590215430897, 14925978329967384, 838829205068709369, 47141595663874099773, 2649323638611897879018, 148890075596000256587991

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OFFSET

1,1

COMMENTS

Column 3 of A208175.

LINKS

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

FORMULA

Empirical: a(n) = 62*a(n-1) - 333*a(n-2) + 396*a(n-3) - 135*a(n-4) for n>5.

Empirical g.f.: x*(5 - 151*x + 276*x^2 - 183*x^3 + 45*x^4) / ((1 - 5*x + 3*x^2)*(1 - 57*x + 45*x^2)). - Colin Barker, Jun 29 2018

EXAMPLE

Some solutions for n=4: