A344585 Numbers whose sum of proper divisors (A001065) is greater than their arithmetic derivative (A003415).

6, 10, 14, 15, 21, 22, 26, 30, 33, 34, 35, 38, 39, 42, 46, 51, 55, 57, 58, 60, 62, 65, 66, 69, 70, 74, 77, 78, 82, 84, 85, 86, 87, 90, 91, 93, 94, 95, 102, 105, 106, 110, 111, 114, 115, 118, 119, 122, 123, 126, 129, 130, 132, 133, 134, 138, 140, 141, 142, 143, 145, 146, 150, 154, 155, 156, 158, 159, 161, 165, 166, 170

Offset

1,1

Comments

Differs from A212168 for the first time at n=100, where a(100) = 221, while A212168(100) = 220. See also comments in A211991.

Links

Antti Karttunen, Table of n, a(n) for n = 1..20000

Prog

(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
isA344585(n) = (A003415(n) < (sigma(n)-n));

Crossrefs

Cf. A001065, A003415, A212168, A344586 (complement).

Positions of negative terms in A211991.

Sequence in context: A362605 A182853 A212168 * A080365 A000469 A120944

Adjacent sequences: A344582 A344583 A344584 * A344586 A344587 A344588

Keyword

nonn

Author

Antti Karttunen, May 24 2021

Status

approved