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%I #13 Jun 14 2020 01:24:39
%S 1,12,24,36,60,72,120,180,240,360,720,1080,1440,1680,2160,2520,3360,
%T 4320,5040,7560,10080,15120,20160,25200,30240,40320,45360,50400,55440,
%U 60480,75600,90720,100800,110880,151200,166320,221760,277200,302400,332640,443520,554400
%N Numbers with a record number of abundant divisors.
%C The corresponding numbers of abundant divisors are 0, 1, 2, 3, 4, 5, 7, 8, 10, 13, 18, 19, 23, ...
%C All the terms > 1 are abundant numbers (A005101) and all the terms > 12 are not primitive abundant numbers (A091191).
%C Apparently, all the terms are least numbers of their prime signature (A025487). This was verified for the first 100 terms.
%H Amiram Eldar, <a href="/A335540/b335540.txt">Table of n, a(n) for n = 1..100</a>
%F Numbers m such that A080224(m) > A080224(k) for all k < m.
%e 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).
%t 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
%Y Cf. A000203, A005101, A025487, A080224, A091191, A091193, A335541, A335542.
%K nonn
%O 1,2
%A _Amiram Eldar_, Jun 13 2020