OFFSET
0,1
COMMENTS
Here 0.p means the decimal fraction obtained by writing p after the decimal point, e.g. 0.11 = 11/100.
The first few values of Sum_{p|n} 0.p are: 1/5, 3/10, 1/5, 1/2, 1/2, 7/10, 1/5, 3/10, 7/10, ...
Subsequence of A005117. - Chai Wah Wu, Sep 15 2016
EXAMPLE
Number 2905 is the smallest number k with floor(Sum_{p|k} 0.p) = 2; set of prime divisors of 2905: {5, 7, 83}; floor(Sum_{p|2905} 0.p) = 0.5 + 0.7 + 0.83 = floor(2.03) = 2.
MATHEMATICA
Table[k = 2; While[f = FactorInteger[k][[All, 1]];
Floor[Total[f*10^-IntegerLength[f]]] != n, k++];
k, {n, 0, 3}] (* Robert Price, Sep 20 2019 *)
PROG
CROSSREFS
KEYWORD
nonn,base,more
AUTHOR
Jaroslav Krizek, Sep 11 2016
EXTENSIONS
a(4) from Michel Marcus, Sep 11 2016
a(5)-a(9) from Giovanni Resta, Aug 31 2019
STATUS
approved