OFFSET
1,4
LINKS
Floris P. van Doorn and Jasper Mulder, Table of n, a(n) for n = 1..20000
MAPLE
with(numtheory):
d:= n-> n*add(i[2]/i[1], i=ifactors(n)[2]):
a:= n-> (f-> `if`(f<2, 0, max(factorset(f)[])))(d(n)):
seq(a(n), n=1..105); # Alois P. Heinz, Jun 08 2015
MATHEMATICA
d[n_] := n*Sum[i[[2]]/i[[1]], {i, FactorInteger[n]}];
a[n_] := Function[f, If[f<2, 0, Max[FactorInteger[f][[All, 1]]]]][d[n]];
Table[a[n], {n, 1, 105}] (* Jean-François Alcover, Mar 23 2017, after Alois P. Heinz *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Jul 23 2003
STATUS
approved