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A167746
Number of prime divisors of A001222 (counted with multiplicity), with a(1) = 1 by convention.
3
1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 2, 0, 1, 0, 1, 1, 1, 0, 2, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 2, 0, 1, 1, 2, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 2, 1, 2, 1, 1, 0, 2, 0, 1, 1, 2, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 2, 1, 0, 2, 1, 1, 1, 2, 0, 2, 1, 1, 1, 1, 1, 2, 0, 1, 1, 2, 0, 1, 0, 2, 1
OFFSET
1,16
COMMENTS
First 31 terms the same as A050370.
FORMULA
a(1) = 1; for n > 1, a(n) = A001222(A001222(n)). - Antti Karttunen, Jul 28 2017
MATHEMATICA
Array[If[# == 1, 1, Nest[PrimeOmega, #, 2]] &, 105] (* Michael De Vlieger, Jul 29 2017 *)
PROG
(Scheme) (define (A167746 n) (if (= 1 n) 1 (A001222 (A001222 n)))) ;; Antti Karttunen, Jul 28 2017
(PARI) a(n) = if (n==1, 1, bigomega(bigomega(n))); \\ Michel Marcus, Jul 28 2017
CROSSREFS
Cf. A001222.
Sequence in context: A052344 A339375 A147768 * A360616 A050370 A050374
KEYWORD
nonn
AUTHOR
EXTENSIONS
Name clarified by Antti Karttunen, Jul 28 2017
STATUS
approved