OFFSET
3,6
FORMULA
EXAMPLE
For n=3, floor(3/2) = 1, phi(3) = 2, gpf(2) = 2, a(3) = 1 - 2 = -1.
For n=107, floor(107/2) = 53, phi(107) = 2*53, gpf(106) = 53, a(107) = 53 - 53 = 0.
For n=128, floor(128/2) = 64, gpf(phi(128)) = gpf(64) = 2, a(128) = 64 - 2 = 62.
MATHEMATICA
mf[x_] := Part[Reverse[Flatten[FactorInteger[x]]], 2] Table[Floor[n/2//N]-mf[EulerPhi[n]], {w, 3, 128}]
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Labos Elemer, May 10 2002
STATUS
approved