A348035 Multiply-perfect numbers k that have a unitary divisor d such that sigma(d)*d = k.

1, 6, 28, 120, 496, 672, 8128, 523776, 33550336, 1379454720, 8589869056, 137438691328, 2305843008139952128, 203820700083634254643200, 2658455991569831744654692615953842176

Offset: 1

Author

Antti Karttunen, Sep 26 2021

Keywords

• nonn

Comments

At least the even terms of A000396 are all present, thus if there are an infinite number of Mersenne primes (A000668), then it implies that this sequence is infinite as well.

Links

• Index entries for sequences related to sigma(n)

Crossrefs

Subsequence of A348031. Intersection of A007691 and A348034.

Cf. A000396, A000668.