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A276651 a(n) = numerator of Sum_{p|n} 0.d where p runs through the prime divisors of n. 6
1, 3, 1, 1, 1, 7, 1, 3, 7, 11, 1, 13, 9, 4, 1, 17, 1, 19, 7, 1, 31, 23, 1, 1, 33, 3, 9, 29, 1, 31, 1, 41, 37, 6, 1, 37, 39, 43, 7, 41, 6, 43, 31, 4, 43, 47, 1, 7, 7, 47, 33, 53, 1, 61, 9, 49, 49, 59, 1, 61, 51, 1, 1, 63, 61, 67, 37, 53, 7, 71, 1, 73, 57, 4, 39 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

COMMENTS

Here 0.d means the decimal fraction obtained by writing d after the decimal point, e.g., 0.11 = 11/100.

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

Jaroslav Krizek, Table of n, a(n) for n = 2..1000

FORMULA

a(n) = (Sum_{p|n} 0.d) * A276652(n) 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) = 1.

PROG

(MAGMA) [Numerator(&+[d/(10^(#Intseq(d))): d in PrimeDivisors(n)]): n in [2..1000]]

CROSSREFS

Cf. A276652, A276653, A276654, A276655, A276513.

Sequence in context: A157964 A140670 A293682 * A185587 A068845 A324910

Adjacent sequences:  A276648 A276649 A276650 * A276652 A276653 A276654

KEYWORD

nonn,base,frac

AUTHOR

Jaroslav Krizek, Sep 10 2016

STATUS

approved

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Last modified July 17 14:44 EDT 2019. Contains 325106 sequences. (Running on oeis4.)