The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

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