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A056464 Number of primitive (aperiodic) palindromes using exactly three different symbols. 3
0, 0, 0, 0, 6, 6, 36, 36, 150, 144, 540, 534, 1806, 1770, 5790, 5760, 18150, 17994, 55980, 55830, 170970, 170466, 519156, 518580, 1569744, 1567944, 4733670, 4732014, 14250606, 14244660, 42850116, 42844320, 128746410, 128728800 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

REFERENCES

M. R. Nester (1999). Mathematical investigations of some plant interaction designs. PhD Thesis. University of Queensland, Brisbane, Australia. [See A056391 for pdf file of Chap. 2]

LINKS

Table of n, a(n) for n=1..34.

FORMULA

sum mu(d)*A056454(n/d) where d|n.

MAPLE

with(numtheory):with(combinat, stirling2):A056454:=n->3!*stirling2(floor((n+1)/2), 3); A056464:=n->add(mobius(d)*A056454(n/d), d=divisors(n)); (C. Ronaldo)

CROSSREFS

Cf. A056459.

Sequence in context: A165827 A256136 A111437 * A056454 A056452 A183622

Adjacent sequences:  A056461 A056462 A056463 * A056465 A056466 A056467

KEYWORD

nonn,base

AUTHOR

Marks R. Nester

STATUS

approved

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Last modified May 26 23:51 EDT 2019. Contains 323597 sequences. (Running on oeis4.)