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Numbers n such that sigma(n) and d(n) are both harmonic (Ore) numbers.
1

%I #8 Dec 15 2017 17:35:55

%S 1,12,76,932,4975,10636,14975,16819,18716,19269,46144,50699,99196,

%T 134975,164421,205916,359232,457792,462272,468032,622436,624211,

%U 812156,879836,1308716,1700991,1872731,2096192,2195776,2275136,2294848,2361152,2366528,3291831

%N Numbers n such that sigma(n) and d(n) are both harmonic (Ore) numbers.

%C 4975 is a term because sigma(4975) = 6200 and d(4975) = 6, both harmonic numbers.

%H Donovan Johnson, <a href="/A071767/b071767.txt">Table of n, a(n) for n = 1..200</a>

%Y Cf. A000005, A000203, A001599.

%K nonn

%O 1,2

%A _Jason Earls_, Jun 04 2002