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A085034 Number of prime factors of cyclotomic(n,9), which is A019327(n), the value of the n-th cyclotomic polynomial evaluated at x=9. 1
3, 2, 2, 2, 3, 1, 2, 3, 3, 2, 4, 1, 2, 2, 3, 2, 5, 1, 4, 1, 4, 2, 3, 3, 4, 2, 5, 2, 6, 1, 5, 2, 3, 2, 3, 1, 5, 2, 8, 2, 5, 2, 3, 3, 5, 2, 7, 2, 7, 4, 5, 2, 5, 1, 5, 3, 6, 2, 4, 3, 4, 3, 5, 2, 4, 1, 5, 3, 7, 3, 6, 2, 6, 3, 7, 4, 4, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The Mobius transform of this sequence yields A057952, number of prime factors of 9^n-1.

REFERENCES

See references at A085021

LINKS

Table of n, a(n) for n=1..78.

MATHEMATICA

Table[Plus@@Transpose[FactorInteger[Cyclotomic[n, 9]]][[2]], {n, 1, 100}]

CROSSREFS

Cf. A019327, A057952, A085021.

Sequence in context: A084402 A127599 A207384 * A119323 A102299 A302481

Adjacent sequences:  A085031 A085032 A085033 * A085035 A085036 A085037

KEYWORD

nonn

AUTHOR

T. D. Noe, Jun 19 2003

STATUS

approved

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Last modified December 7 00:16 EST 2019. Contains 329812 sequences. (Running on oeis4.)