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A211694 Number of nonnegative integer arrays of length n+2*2-2 with new values introduced in order 0 upwards and every value appearing only in runs of at least 2 3
1, 2, 3, 6, 11, 23, 47, 103, 226, 518, 1200, 2867, 6946, 17234, 43393, 111419, 290242, 768901, 2065172, 5630083, 15549403, 43527487, 123343911, 353864422, 1026935904, 3014535166, 8945274505, 26829206798, 81293234754, 248805520401, 768882019073 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 2 of A211700

LINKS

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

FORMULA

G.f.: 1/x/W(0)-1/x, where W(k) = 1 - x - x^2/(1 - x^2*(k+1)/W(k+1) ); (continued fraction). - Sergei N. Gladkovskii, Nov 10 2014

EXAMPLE

All solutions for n=5

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

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

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

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

..1....1....2....1....1....0....1....0....0....1....1

..2....1....2....0....2....0....1....1....0....1....0

..2....1....2....0....2....0....1....1....0....1....0

G.f. = x + 2*x^2 + 3*x^3 + 6*x^4 + 11*x^5 + 23*x^6 + 47*x^7 + 103*x^8 + ...

CROSSREFS

Cf. A160823.

Sequence in context: A198620 A198648 A198655 * A303586 A130131 A338355

Adjacent sequences:  A211691 A211692 A211693 * A211695 A211696 A211697

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 19 2012

STATUS

approved

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Last modified December 5 10:11 EST 2021. Contains 349543 sequences. (Running on oeis4.)