A353765 Numbers k for which A353749(k) is a multiple of A353749(sigma(k)), where A353749(k) = phi(k) * A064989(k), and A064989 shifts the prime factorization one step towards lower primes.

1, 3, 5, 15, 27, 459, 819, 2295, 13923, 69615, 361179, 3282147, 6140043, 16410735, 30700215, 99558459, 277788987, 497792295, 1388944935

Offset: 1

Author

Antti Karttunen, May 10 2022

Keywords

• nonn
• more

Comments

Question: Does every term need to be odd? Could there be any other non-multiples of 3 than a(1) and a(3)?

If it exists, a(20) > 2^32.

Links

• Index entries for sequences where odd perfect numbers must occur, if they exist at all
• Index entries for sequences computed from indices in prime factorization
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A000010, A000203, A006872, A062401, A064989, A336549, A336550, A353757, A353761.

Positions of 1's in A353763. Cf. also A353764.

Conjectured to be a subsequence of A353758.