OFFSET
1,2
COMMENTS
The corresponding numbers of abundant divisors are 0, 1, 2, 3, 4, 5, 7, 8, 10, 13, 18, 19, 23, ...
All the terms > 1 are abundant numbers (A005101) and all the terms > 12 are not primitive abundant numbers (A091191).
Apparently, all the terms are least numbers of their prime signature (A025487). This was verified for the first 100 terms.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..100
EXAMPLE
12 is in the sequence since it is the least number with one abundant divisor (12). The next number with more than one abundant divisor is 24 which has 2 abundant divisors (12 and 24).
MATHEMATICA
s[n_] := Count[Divisors[n], _?(DivisorSigma[1, #] > 2*# &)]; sm = -1; seq = {}; Do[s1 = s[n]; If[s1 > sm, sm = s1; AppendTo[seq, n]], {n, 1, 10^6}]; seq
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Jun 13 2020
STATUS
approved