A356303 The least k >= 0 such that n and A276086(n-k) are relatively prime, where A276086 is the primorial base exp-function.

0, 0, 0, 2, 0, 0, 0, 0, 0, 2, 6, 0, 0, 0, 0, 14, 0, 0, 0, 0, 16, 2, 0, 0, 0, 20, 0, 2, 0, 0, 0, 0, 0, 2, 0, 30, 0, 0, 0, 2, 6, 0, 18, 0, 0, 14, 0, 0, 0, 20, 16, 2, 0, 0, 0, 20, 28, 2, 0, 0, 0, 0, 0, 38, 0, 0, 0, 0, 0, 2, 66, 0, 0, 0, 0, 14, 0, 48, 0, 0, 16, 2, 0, 0, 60, 20, 0, 2, 0, 0, 0, 62, 0, 2, 0, 0, 0, 0, 70, 2, 6

Offset: 0

Author

Antti Karttunen, Nov 03 2022

Keywords

• nonn
• look

Comments

All terms are even.

Links

• Antti Karttunen, Table of n, a(n) for n = 0..11550
• Antti Karttunen, Data supplement: n, a(n) computed for n = 0..65537
• Antti Karttunen, Scatter plot up to n=65537
• Index entries for sequences related to primorial base

Crossrefs

Cf. A276086, A324198.

Cf. A324583 (positions of zeros).

Cf. also A356302, A356305.

Programs

PARI

A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A356303(n) = { my(k=0); while(gcd(A276086(n-k),n)!=1,k++); (k); };