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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
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)).
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
Sequence in context: A222656 A162545 A162544 * A083647 A364332 A346389
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Jan 19 2013
STATUS
approved