A326807 Numbers m such that s(m)/m > s(k)/k for all k < m, where s(m) = A168512(m) is the sum of divisors of m, weighted by divisor multiplicity.

1, 2, 4, 8, 12, 16, 24, 36, 72, 120, 180, 240, 360, 720, 840, 1260, 1680, 2520, 5040, 10080, 15120, 25200, 27720, 55440, 110880, 166320, 277200, 332640, 554400, 665280, 720720, 1441440, 2162160, 3603600, 4324320, 7207200, 8648640, 10810800, 21621600, 36756720, 61261200, 73513440

Offset

1,2

Comments

The least number m such that A168512(m)/m > k, for k = 2, 3, ... is 4, 120, 27720, 122522400, ...

Links

Table of n, a(n) for n=1..42.

Mathematica

s[n_] := 1 + DivisorSum[n, #*IntegerExponent[n, #] &, # > 1 &]; seq = {}; sm = 0; Do[s1 = s[n]/n; If[s1 > sm, sm = s1; AppendTo[seq, n]], {n, 1, 100000000}]; seq (* after Michael De Vlieger at A168512 *)

Crossrefs

Cf. A004394, A168512, A326677, A326712.

Sequence in context: A170892 A246468 A360641 * A052184 A152768 A266047

Adjacent sequences: A326804 A326805 A326806 * A326808 A326809 A326810

Keyword

nonn

Author

Amiram Eldar, Oct 19 2019

Status

approved