A354073 - OEIS

A354073

Multiply-perfect numbers that are the sum of the divisors of some number.

1, 6, 28, 120, 496, 672, 30240, 32760, 523776, 2178540, 23569920, 33550336, 45532800, 142990848, 459818240, 1379454720, 1476304896, 8589869056, 14182439040, 31998395520, 43861478400, 51001180160, 66433720320, 137438691328, 153003540480, 403031236608, 518666803200

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OFFSET

1,2

COMMENTS

Conjecture: 8128 is only multiply-perfect number that is not in this sequence.

The distinct values of A000203(A066961(n)).

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..50

EXAMPLE

The multiply-perfect number 28 is in the sequence because 28 = sigma(12).

PROG

(Magma) Set(Sort([&+Divisors(m): m in [1..10^7] | IsIntegral(&+Divisors(&+Divisors(m)) / &+Divisors(m))]))