A211842 - OEIS

A211842

Number of nonnegative integer arrays of length n+3 with new values 0 upwards introduced in order, no three adjacent elements all unequal, and containing the value 2.

1, 5, 19, 63, 196, 588, 1731, 5049, 14689, 42809, 125364, 369678, 1099339, 3300091, 10006487, 30658799, 94932890, 297079702, 939477265, 3001846219, 9689289277, 31586215805, 103968208826, 345457027212, 1158435912189, 3919502591649

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OFFSET

1,2

COMMENTS

Column 1 of A211849.

LINKS

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

EXAMPLE

Some solutions for n=3

..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

..1....1....1....1....0....1....0....1....0....1....1....1....0....1....0....1

..1....1....1....1....1....0....1....1....1....0....1....1....0....0....1....1