OFFSET
3,1
COMMENTS
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 3..1000
Paul Yiu, Recreational Mathematics, 24.3.1 Appendix: Two enumerations of the rational numbers in (0,1), page 633.
EXAMPLE
See A245677.
PROG
(Haskell)
import Data.Ratio ((%), denominator)
a245678 n = denominator $ sum
[num % den | num <- [1 .. div n 2], let den = n - num, gcd num den == 1]
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
Reinhard Zumkeller, Jul 30 2014
STATUS
approved