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%I #15 Oct 20 2022 09:10:39
%S 20,70,272,550,945,1575,3465,15015,47025,81081,153153,692835,1851759,
%T 3633903,6084351,22309287,95009481,131339637,277272567,1321122231,
%U 1516844043,5391411025,28816162375,40342627325,181667110625,186096635725,213239601575
%N Primitive abundant numbers that set a new record for number of divisors.
%t abQ[n_] := DivisorSigma[-1, n] > 2; defQ[n_] := DivisorSigma[-1, n] < 2; primQ[n_] := abQ[n] && AllTrue[n/FactorInteger[n][[;; , 1]], defQ]; s = {}; dm = 0; Do[If[(d = DivisorSigma[0, n]) > dm && primQ[n], dm = d; AppendTo[s, n]], {n, 1, 10^6}]; s (* _Amiram Eldar_, Oct 20 2022 *)
%Y Cf. A000005, A071395.
%K nonn
%O 1,1
%A _Jason Earls_, Jun 18 2003
%E More terms from Lambert Herrgesell (zero815(AT)googlemail.com), Jan 02 2006
%E a(20)-a(24) from _Donovan Johnson_, Apr 09 2010
%E a(25)-a(27) from _Donovan Johnson_, Oct 21 2012
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