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A206452
Number of 0..5 arrays of length n avoiding the consecutive pattern 0..5.
2
6, 36, 216, 1296, 7776, 46655, 279924, 1679508, 10076832, 60459696, 362750400, 2176455745, 13058454546, 78349047768, 470084209776, 2820444798960, 16922306043360, 101531659804415, 609176900371944, 3654983053183896
OFFSET
1,1
COMMENTS
Column 5 of A206455.
FORMULA
a(n) = 6*a(n-1) - a(n-6).
Empirical: a(n) = Sum_{i=0..floor(n/6)} ((-1)^i*6^(n-6*i)*binomial(n-5*i,i)).
g.f.: x*(6 - x^5) / (1 - 6*x + x^6). - Colin Barker, Jun 16 2018
CROSSREFS
Cf. A206455.
Sequence in context: A126634 A216128 A007275 * A215748 A000400 A238936
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 07 2012
STATUS
approved