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A243515 Number of length n+2 0..6 arrays with no three elements in a row with pattern aba or abb (with a!=b) and new values 0..6 introduced in 0..6 order. 1
3, 5, 10, 25, 77, 279, 1134, 4979, 22981, 109453, 531458, 2610933, 12917685, 64181627, 319695982, 1594859887, 7963472189, 39784944801, 198827606706, 993846943841, 4968361974493, 24839192686975, 124188113975630 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 12*a(n-1) - 52*a(n-2) + 102*a(n-3) - 91*a(n-4) + 30*a(n-5).

Conjectures from Colin Barker, Nov 02 2018: (Start)

G.f.: x*(3 - 31*x + 106*x^2 - 141*x^3 + 60*x^4) / ((1 - x)^2*(1 - 2*x)*(1 - 3*x)*(1 - 5*x)).

a(n) = (147 + 2^(5+n) + 4*3^(1+n) + 5^n + 36*n) / 96.

(End)

EXAMPLE

All solutions for n=3:

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

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

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

..3....2....3....1....0....3....0....0....2....0

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

CROSSREFS

Column 6 of A243519.

Sequence in context: A243513 A002039 A243514 * A243516 A243517 A243518

Adjacent sequences:  A243512 A243513 A243514 * A243516 A243517 A243518

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 05 2014

STATUS

approved

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Last modified June 19 12:47 EDT 2021. Contains 345129 sequences. (Running on oeis4.)