A373476 Numbers k such that k, A001414(k) and A083345(k) are all multiples of 3, where A001414 is fully additive with a(p) = p, and A083345 is the numerator of the fully additive function with a(p) = 1/p.

19683, 157464, 275562, 393660, 511758, 688905, 747954, 866052, 984150, 1220346, 1259712, 1279395, 1338444, 1456542, 1515591, 1692738, 1810836, 1869885, 2165130, 2204496, 2283228, 2342277, 2401326, 2460375, 2637522, 2814669, 2873718, 3050865, 3109914, 3149280, 3168963, 3228012, 3346110, 3641355, 3700404, 3818502

Offset: 1

Author

Antti Karttunen, Jun 06 2024

Keywords

• nonn

Comments

Numbers k such that A373474(k) = 1+A369658(k).

All terms are multiples of 19683 [= 3^9].

Links

• Antti Karttunen, Table of n, a(n) for n = 1..23455; terms less than 2^21

Crossrefs

Intersection of A008585 and A373475.

Setwise difference A373475 \ A369659.

Cf. A001414, A083345, A369658, A369659, A373474.

Programs

PARI

A001414(n) = ((n=factor(n))[, 1]~*n[, 2]); \\ From A001414.
A083345(n) = { my(f=factor(n)); numerator(vecsum(vector(#f~, i, f[i, 2]/f[i, 1]))); };
isA373476(n) = (!(n%3) && !(A001414(n)%3) && !(A083345(n)%3));

Formula

a(n) = 3^9 * A373475(n).