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A209323 Values of omega(n) (A001221) as n runs through the triprimes (A014612). 2
1, 2, 2, 2, 1, 2, 3, 3, 2, 2, 2, 2, 2, 3, 2, 3, 2, 2, 3, 2, 2, 2, 3, 3, 3, 3, 2, 2, 2, 1, 3, 3, 2, 2, 2, 3, 2, 3, 3, 2, 2, 3, 2, 3, 3, 2, 3, 3, 2, 2, 3, 3, 3, 2, 3, 2, 2, 2, 3, 3, 3, 2, 3, 2, 3, 2, 2, 3, 2, 3, 3, 3, 2, 3, 2, 3, 3, 2, 2, 2, 2, 1, 3, 3, 2, 3, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

omega(n) is the number of distinct prime divisors of n. A number is triprime if it has exactly 3 (not necessarily distinct) prime divisors.

a(n) = omega(A014612(n)).

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

EXAMPLE

First triprime = 8, has 1 distinct prime divisor (2) so a(1) = 1.

MATHEMATICA

t = {}; Do[f = FactorInteger[n]; If[Total[Transpose[f][[2]]] == 3, AppendTo[t, Length[f]]], {n, 400}]; t (* T. D. Noe, Jan 23 2013 *)

CROSSREFS

Cf. A001221, A014612.

Sequence in context: A222656 A162545 A162544 * A083647 A056691 A262982

Adjacent sequences:  A209320 A209321 A209322 * A209324 A209325 A209326

KEYWORD

nonn

AUTHOR

Wesley Ivan Hurt, Jan 19 2013

STATUS

approved

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Last modified May 10 21:08 EDT 2021. Contains 343780 sequences. (Running on oeis4.)