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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. 0
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
The least number m such that A168512(m)/m > k, for k = 2, 3, ... is 4, 120, 27720, 122522400, ...
LINKS
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
Sequence in context: A170892 A246468 A360641 * A052184 A152768 A266047
KEYWORD
nonn
AUTHOR
Amiram Eldar, Oct 19 2019
STATUS
approved

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Last modified April 19 07:11 EDT 2024. Contains 371782 sequences. (Running on oeis4.)