A088847 a(n) = sigma(A087979(n)) / phi(A087979(n)).

1, 1, 3, 4, 4, 6, 6, 8, 9, 8, 10, 12, 12, 14, 15, 16, 16, 18, 18, 20, 21, 20, 22, 24, 25, 24, 27, 28, 28, 30, 30, 32, 33, 32, 35, 36, 36, 36, 39, 40, 40, 42, 42, 44, 45, 46, 46, 48, 49, 50, 51, 52, 52, 54, 55, 56, 57, 56, 58, 60, 60, 62, 63, 64, 65, 66, 66, 68, 69, 70, 70, 72, 72, 74, 75, 76, 77, 78, 79, 80, 81, 82, 82, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100

Offset: 1

Author

Labos Elemer, Nov 17 2003

Keywords

• nonn

Comments

Note that A087979(n) is a balanced number (A020492), hence this sequence is well-defined. - Max Alekseyev, Oct 10 2024

For all n, a(n) <= n and a(n) divides A299822(n). - Max Alekseyev, Oct 11 2024

Examples

			While A088830 includes special balanced numbers, A087979 does not include per definition. Nevertheless, it seems that A087979 consists only of balanced numbers. This is provable at least for special cases.
		

Crossrefs

Cf. A000010, A000203, A087979, A020492, A088830, A299822.

Extensions

a(24)-a(35) from Amiram Eldar, Dec 05 2019 (calculated from the data at A087979)

Terms a(36) onward from Max Alekseyev, Oct 10 2024