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 A085035 Number of prime factors of cyclotomic(n,10), which is A019328(n), the value of the n-th cyclotomic polynomial evaluated at x=10. 3
 2, 1, 2, 1, 2, 2, 2, 2, 2, 1, 2, 1, 3, 1, 2, 2, 2, 2, 1, 2, 3, 4, 1, 1, 3, 2, 3, 3, 5, 3, 3, 5, 2, 3, 3, 1, 3, 1, 1, 2, 4, 4, 4, 3, 2, 4, 2, 1, 2, 3, 4, 2, 4, 2, 4, 2, 3, 2, 2, 3, 7, 1, 5, 4, 2, 2, 3, 3, 3, 2, 2, 3, 3, 3, 3, 2, 4, 5, 6, 2, 6, 2, 3, 2, 3, 3, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The Mobius transform of this sequence yields A057951, number of prime factors of 10^n-1. REFERENCES See references at A085021. LINKS Ray Chandler, Table of n, a(n) for n = 1..322 Makoto Kamada, Factorizations of Phi_n(10) FORMULA a(n) = A001222(A019328(n)). - Ray Chandler, May 10 2017 MATHEMATICA Table[Plus@@Transpose[FactorInteger[Cyclotomic[n, 10]]][[2]], {n, 1, 100}] CROSSREFS Cf. A001222, A019328, A057951, A085021. Sequence in context: A219181 A260341 A109969 * A198333 A191591 A083023 Adjacent sequences:  A085032 A085033 A085034 * A085036 A085037 A085038 KEYWORD nonn AUTHOR T. D. Noe, Jun 19 2003 STATUS approved

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Last modified February 21 03:06 EST 2019. Contains 320364 sequences. (Running on oeis4.)