A391863 Numbers k that are coprime to A276085(k) and that are not divisible by p^p for any prime p, where A276085 is the primorial base log-function.

1, 2, 3, 5, 7, 9, 10, 11, 13, 14, 15, 17, 18, 19, 21, 22, 23, 25, 26, 29, 31, 33, 34, 35, 37, 39, 41, 43, 46, 47, 49, 50, 51, 53, 55, 57, 58, 59, 61, 62, 63, 65, 67, 69, 70, 71, 73, 74, 75, 77, 79, 82, 83, 85, 86, 87, 89, 90, 93, 94, 95, 97, 98, 99, 101, 103, 105, 106, 107, 109, 110, 111, 113, 115, 118, 119, 121

Offset

1,2

Comments

Sequence A276086(A324583(.)) sorted into ascending order.

Links

Antti Karttunen, Table of n, a(n) for n = 1..10000

Formula

{k such that A359550(k)*A373361(k) = 1}.

Prog

(PARI)
A276085(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*prod(i=1, primepi(f[k, 1]-1), prime(i))); };
A359550(n) = { my(pp); forprime(p=2, , pp = p^p; if(!(n%pp), return(0)); if(pp > n, return(1))); };
is_A391863(n) = (A359550(n) && (1==gcd(n, A276085(n))));

Crossrefs

Cf. A276085, A276086, A324583, A359550, A373361.

Intersection of A048103 and A391862.

Cf. also A391866.

Sequence in context: A304721 A063464 A341518 * A387710 A325600 A195921

Adjacent sequences: A391860 A391861 A391862 * A391864 A391865 A391866

Keyword

nonn

Author

Antti Karttunen, Jan 16 2026

Status

approved