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A082343 Numerator of sopfr(n)/n, where sopfr=A001414 is the sum of prime factors (with repetition). 4
0, 1, 1, 1, 1, 5, 1, 3, 2, 7, 1, 7, 1, 9, 8, 1, 1, 4, 1, 9, 10, 13, 1, 3, 2, 15, 1, 11, 1, 1, 1, 5, 14, 19, 12, 5, 1, 21, 16, 11, 1, 2, 1, 15, 11, 25, 1, 11, 2, 6, 20, 17, 1, 11, 16, 13, 22, 31, 1, 1, 1, 33, 13, 3, 18, 8, 1, 21, 26, 1, 1, 1, 1, 39, 13, 23, 18, 3, 1, 13, 4, 43, 1, 1, 22, 45, 32, 17 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,6
COMMENTS
Denominator is A082344(n) = n/A082299(n).
LINKS
FORMULA
a(n) = A001414(n)/A082299(n).
EXAMPLE
n=200: (2+2+2+5+5)/(2*2*2*5*5) = 16/(2*2*2*5*5) = (2*2*2*2)/(2*2*2*5*5) = 2/25, therefore a(200)=2, A082344(200)=25.
MATHEMATICA
sopfr[n_] := If[n == 1, 0, Total[Times @@@ FactorInteger[n]]];
a[n_] := Numerator[sopfr[n]/n];
Array[a, 100] (* Jean-François Alcover, Dec 03 2021 *)
PROG
(PARI)
A001414(n) = ((n=factor(n))[, 1]~*n[, 2]); \\ From A001414.
A082299(n) = gcd(n, A001414(n));
A082343(n) = A001414(n)/A082299(n); \\ Antti Karttunen, Mar 04 2018
CROSSREFS
Sequence in context: A068237 A083345 A087262 * A166125 A199074 A343235
KEYWORD
nonn,frac
AUTHOR
Reinhard Zumkeller, Apr 09 2003
STATUS
approved

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Last modified April 24 07:35 EDT 2024. Contains 371922 sequences. (Running on oeis4.)