%I #8 Jul 02 2019 15:28:56
%S 672,2016,69300,146160,207900,1627920,8316000,9828000,38253600,
%T 60147360,105814800,158004000,726818400,95935039200,191870078400,
%U 2206505901600,3463953292800,3800093497200,4413011803200,7600186994400,8826023606400
%N Numbers between a pair of consecutive highly abundant numbers (A002093) having the same sum of divisors as the lesser one.
%C Define "largely abundant numbers" to be numbers k such that sigma(k) >= sigma(j) for all j < k. This sequence gives all the largely abundant numbers that are not highly abundant numbers.
%C Analogous to A244353 as A002093 is analogous to A002182.
%C No more terms below 10^10.
%C a(22) > 10^13. - _Giovanni Resta_, Jul 02 2019
%e 672 is in the sequence since 660 < 672 < 720, (660, 720) are a pair of consecutive highly abundant numbers, and sigma(672) = sigma(660) = 2016.
%t s={}; sm=0; Do[s1=DivisorSigma[1,n]; If[s1==sm, AppendTo[s,n]]; If[s1>sm, sm=s1], {n,1,10^5}]; s
%Y Cf. A002093, A002182, A067128, A244353.
%K nonn,more
%O 1,1
%A _Amiram Eldar_, Jun 08 2019
%E a(14)-a(21) from _Giovanni Resta_, Jul 02 2019
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