A379498 a(n) = A276086(1+n) - A276086(A001065(n)), where A276086 is the primorial base exp-function, and A001065 is the sum of proper divisors of n.

2, 4, 7, 12, 3, 5, 13, 20, 36, 75, 23, -175, 73, 105, 195, 300, 123, -500, 373, -375, 1035, 2175, 623, 1215, 1870, 3525, 5575, 5625, 5, -161, 19, 28, -87, -249, -15, -8680, 103, -915, -135, -1995, 173, -4025, 523, 735, 1533, 1275, 873, -9275, 2610, 4900, 7125, 14175, 4373, 8505, 12675, 25809, 37125, 78729, 47

Offset: 1

Author

Antti Karttunen, Jan 05 2025

Keywords

• sign

Links

• Antti Karttunen, Table of n, a(n) for n = 1..30030
• Index entries for sequences related to primorial base.
• Index entries for sequences related to sigma(n).

Crossrefs

Cf. A001065, A276086, A379493, A379494.

Cf. also A379496.

Programs

PARI

A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A379498(n) = (A276086(1+n) - A276086(sigma(n)-n));

Formula

a(n) = A276086(1+n) - A379493(n).

For even n, a(n) = A379494(n).