OFFSET
1,7
COMMENTS
Numerator of n / A005940(n).
LINKS
MATHEMATICA
nn = 89; Array[Set[a[#], #] &, 2]; Do[If[EvenQ[n], Set[a[n], 2 a[n/2]], Set[a[n], Times @@ Power @@@ Map[{Prime[PrimePi[#1] + 1], #2} & @@ # &, FactorInteger[a[(n + 1)/2]]]]], {n, 3, nn}], n]; Array[#/GCD[a[#], #] &, nn] (* Michael De Vlieger, Jul 28 2023 *)
PROG
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
Antti Karttunen, Jul 28 2023
STATUS
approved