OFFSET
1,2
LINKS
Peter Andrew, Table of n, a(n) for n = 1..20000
FORMULA
a(n) = n <=> n in { A067128 }. - Alois P. Heinz, Jun 11 2020
MAPLE
a:= proc(n) option remember; uses numtheory; `if`(n=1, 1,
(t-> `if`(tau(n)<tau(t), t, n))(a(n-1)))
end:
seq(a(n), n=1..100); # Alois P. Heinz, Jun 11 2020
MATHEMATICA
dmax = 0; nmax = 1; seq = {}; Do[If[(d = DivisorSigma[0, n]) >= dmax, dmax = d; nmax = n]; AppendTo[seq, nmax], {n, 1, 72}]; seq (* Amiram Eldar, Jun 11 2020 *)
PROG
(Haskell) a329004 = map fst $ scanl1 (\x y -> maximumBy (comparing snd) [x, y]) $ zip [1..] a000005
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Andrew, Jun 10 2020
STATUS
approved