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%I #24 Aug 19 2018 10:43:27
%S 1,20,45,320,6615,382200,680890228200,8169778639360,27445575588992,
%T 56626123593600,1235050901504640
%N Numbers such that the sum of unitary divisors (A034448) is equal to the sum of exponential divisors (A051377).
%C Following numbers also belongs to this sequence, however their actual positions are unknown: 3640527948039840, 181552482521182080, 19736989888296320640, 108455561012908979640, 796015410768776072160, 4220107447484548287360, 39697147230528075361920, 202868762331595335655680, 668431747385354202124160, 124402428235930297906738935, 2456687209744634987008753664.
%H Tim Trudgian, <a href="http://arxiv.org/abs/1312.4615">The sum of the unitary divisor function</a>, arXiv:1312.4615 [math.NT], 2013-2014 (see page 6).
%H Tim Trudgian, <a href="https://www.emis.de/journals/PIMB/111/16.html">The sum of the unitary divisor function</a>, Publications de l'Institut Mathématique (Beograd), Vol. 97(111), 2015.
%e The e-divisors of 20 are 10 and 20, sum 30, and its unitary divisors are 1, 4, 5, and 20, also sum 30.
%e For n=320=2^6*5 we have A051377(n)=(2^6+2^3+2^2+2)*5 = 390 and A034448(n)=(2^6+1)*(5+1) = 390 again.
%Y Cf. A034448, A051377.
%K nonn,more
%O 1,2
%A _Michel Marcus_, Jan 29 2014
%E More terms from _Andrew Lelechenko_, Feb 06 2014
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