A356167 Greatest common divisor of A003961(n) and the smallest positive k such that n divides k*A003961(k), where A003961 is fully multiplicative with a(p) = nextprime(p).

1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 5, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 5, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 7, 1, 1, 1, 1, 3, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 5, 1, 1, 1, 1, 1, 3, 11, 1, 1, 1, 1, 1, 1, 1, 1, 9, 1, 1, 1, 1, 5

Offset: 1

Author

Antti Karttunen, Jul 28 2022

Keywords

• nonn
• look

Links

• Antti Karttunen, Table of n, a(n) for n = 1..65537
• Index entries for sequences computed from indices in prime factorization

Crossrefs

Cf. A003961, A191002, A356164, A356165, A356166.

Cf. also A345993.

Programs

PARI

A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A356167(n) = for(k=1, oo, if((k*A003961(k))%n==0, return(gcd(A003961(n),k))));

Formula

a(n) = gcd(A003961(n), A356164(n)).