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A242235 Number of length n+4+1 0..4 arrays with every value 0..4 appearing at least once in every consecutive 4+2 elements, and new values 0..4 introduced in order. 1
15, 35, 71, 139, 271, 531, 1047, 2059, 4047, 7955, 15639, 30747, 60447, 118835, 233623, 459291, 902943, 1775139, 3489831, 6860827, 13488031, 26516771, 52130599, 102486059, 201482287, 396103747, 778719463, 1530922155, 3009713711 (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) = a(n-1) + a(n-2) + a(n-3) + a(n-4) + a(n-5).

Conjecture: a(n) = 16*A145113(n-1) + A004767(n-2), n > 1. - R. J. Mathar, Aug 16 2017

Empirical g.f.: x*(15 + 20*x + 21*x^2 + 18*x^3 + 11*x^4) / (1 - x - x^2 - x^3 - x^4 - x^5). - Colin Barker, Oct 31 2018

EXAMPLE

Some solutions for n=5:

  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0

  0  1  1  1  1  1  1  1  1  0  1  1  0  1  1  1

  1  2  2  2  2  0  2  0  0  1  2  2  1  2  2  2

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

  3  2  3  3  4  3  0  3  3  3  3  4  3  3  0  3

  4  4  4  4  1  4  4  4  4  4  4  1  4  4  4  4

  1  0  1  0  0  1  1  0  0  2  0  0  0  0  1  2

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

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

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

CROSSREFS

Cf. A004767, A145113, A242239.

Column 4 of A242239.

Sequence in context: A160497 A098271 A234542 * A082663 A109068 A334309

Adjacent sequences:  A242232 A242233 A242234 * A242236 A242237 A242238

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 08 2014

STATUS

approved

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Last modified June 24 18:46 EDT 2021. Contains 345419 sequences. (Running on oeis4.)