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A046987 Multiply perfect numbers whose average divisor is (a) not an integer and (b) does not divide the number itself. 5

%I

%S 120,523776,1476304896,31998395520,30823866178560,

%T 69357059049509038080,4010059765937523916800,27099073228001299660800,

%U 686498980761986918441287680,2827987212986831882236723200

%N Multiply perfect numbers whose average divisor is (a) not an integer and (b) does not divide the number itself.

%F a=s1/s0, b=x/a, c=s1/x, where s1 is the sum and s0 is the number of divisors of x. Here only c is an integer, while a and b are not.

%e x=523776,number of divisors is 80, Sigma[ 1,523776 ]=1571328 and the relevant quotients are: a=19641.6, b=26.667, c=3(integer).

%Y In A007691 but not in A003601 or A001599. Cf. A046985, A046986.

%K nonn

%O 1,1

%A _Labos Elemer_

%E a(5)-a(10) from _Donovan Johnson_, Nov 30 2008

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Last modified October 23 23:51 EDT 2019. Contains 328379 sequences. (Running on oeis4.)