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A276652 a(n) = denominator of Sum_{p|n} 0.d where p runs through the prime divisors of n. 6
5, 10, 5, 2, 2, 10, 5, 10, 10, 100, 2, 100, 10, 5, 5, 100, 2, 100, 10, 1, 100, 100, 2, 2, 100, 10, 10, 100, 1, 100, 5, 100, 100, 5, 2, 100, 100, 100, 10, 100, 5, 100, 100, 5, 100, 100, 2, 10, 10, 100, 100, 100, 2, 100, 10, 100, 100, 100, 1, 100, 100, 1, 5, 100 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,1
COMMENTS
The first few values of Sum_{p|n} 0.d are: 1/5, 3/10, 1/5, 1/2, 1/2, 7/10, 1/5, 3/10, 7/10, ...
See A276655 - numbers n such that Sum_{p|n} 0.d is an integer.
LINKS
FORMULA
a(n) = A276651(n) / (Sum_{p|n} 0.d) where p = prime divisors of n.
EXAMPLE
For n=12; Sum_{p|12} 0.d = 0.2 + 0.3 = 0.5 = 5/10 = 1/2; a(12) = 2.
MATHEMATICA
Denominator[Table[f = FactorInteger[i][[All, 1]];
Total[f*10^-IntegerLength[f]], {i, 2, 65}]] (* Robert Price, Sep 20 2019 *)
PROG
(Magma) [Denominator(&+[d/(10^(#Intseq(d))): d in PrimeDivisors(n)]): n in [2..1000]]
CROSSREFS
Sequence in context: A357913 A053822 A262922 * A137404 A110643 A010721
KEYWORD
nonn,base,frac
AUTHOR
Jaroslav Krizek, Sep 10 2016
STATUS
approved

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Last modified March 29 03:51 EDT 2024. Contains 371264 sequences. (Running on oeis4.)