A324873 a(n) = gcd(n, A060968(n)).

1, 2, 1, 4, 1, 2, 1, 8, 3, 2, 1, 4, 1, 2, 1, 16, 1, 6, 1, 4, 1, 2, 1, 8, 5, 2, 9, 4, 1, 2, 1, 32, 3, 2, 1, 12, 1, 2, 3, 8, 1, 2, 1, 4, 3, 2, 1, 16, 7, 10, 1, 4, 1, 18, 1, 8, 1, 2, 1, 4, 1, 2, 3, 64, 1, 6, 1, 4, 3, 2, 1, 24, 1, 2, 5, 4, 1, 6, 1, 16, 27, 2, 1, 4, 1, 2, 1, 8, 1, 6, 1, 4, 1, 2, 5, 32, 1, 14, 9, 20, 1, 2, 1, 8, 1

Offset: 1

Author

Antti Karttunen, May 18 2019

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..65537

Crossrefs

Cf. A060968, A235866 (positions of ones).

Programs

PARI

A060968(n) = { my(f=factor(n)[, 1]); n*prod(i=if(n%2, 1, 2), #f, if(f[i]%4==1, 1-1/f[i], 1+1/f[i]))*if(n%4, 1, 2); }; \\ From A060968
A324873(n) = gcd(n,A060968(n));

Formula

a(n) = gcd(n, A060968(n)).