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A088530
Denominator of bigomega(n)/omega(n).
27
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 1, 2, 1, 1, 1, 3, 1, 1, 1, 1, 1, 3, 1, 2, 1, 1, 1, 1, 1, 2, 2, 1
OFFSET
2,11
COMMENTS
a(n) is the denominator of A022559(n)/A000720(n). - Robert Israel, Jan 08 2024
FORMULA
Let B = number of prime divisors of n with multiplicity, O = number of distinct prime divisors of n. Then a(n) = denominator of B/O.
EXAMPLE
bigomega(24) / omega(24) = 4/2 = 2/1, so a(24) = 1.
MAPLE
N:= 100:
W:= ListTools:-PartialSums(map(numtheory:-bigomega, [$1..N])):
seq(denom(W[i]/numtheory:-pi(i)), i=2..N); # Robert Israel, Jan 08 2024
MATHEMATICA
Table[Denominator[PrimeOmega[n]/PrimeNu[n]], {n, 2, 100}] (* Harvey P. Dale, Mar 22 2012 *)
PROG
(PARI) for(x=2, 100, y=bigomega(x)/omega(x); print1(denominator(y)", "))
(Python)
from sympy import primefactors, Integer
def bigomega(n): return 0 if n==1 else bigomega(Integer(n)/primefactors(n)[0]) + 1
def omega(n): return Integer(len(primefactors(n)))
def a(n): return (bigomega(n)/omega(n)).denominator()
print([a(n) for n in range(2, 51)]) # Indranil Ghosh, Jul 13 2017
CROSSREFS
Cf. A001221, A001222, A000720, A022559, A070012, A070013, A070014, A088529 (gives the numerator).
Sequence in context: A330749 A294883 A348940 * A058060 A338160 A336137
KEYWORD
nonn,frac,look
AUTHOR
Cino Hilliard, Nov 16 2003
STATUS
approved