A353763 a(n) = A353750(n) / gcd(A353749(n), A353750(n)).

1, 4, 1, 15, 1, 2, 2, 12, 11, 2, 4, 15, 5, 8, 1, 435, 3, 22, 4, 5, 2, 24, 8, 6, 29, 10, 1, 2, 12, 2, 8, 45, 4, 9, 4, 165, 17, 16, 5, 6, 3, 8, 10, 12, 11, 48, 16, 435, 204, 58, 3, 175, 36, 4, 4, 8, 4, 72, 48, 5, 29, 32, 11, 7119, 5, 24, 208, 45, 8, 8, 48, 66, 31, 34, 29, 20, 16, 10, 16, 145, 2695, 18, 120, 2, 3, 40

Offset: 1

Author

Antti Karttunen, May 10 2022

Keywords

• nonn
• frac

Comments

Denominator of ratio A353749(n) / A353750(n).

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10000
• Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537
• Index entries for sequences computed from indices in prime factorization
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A000010, A000203, A006872, A062401, A064989, A336549, A336550, A353757, A353761, A353762 (numerators), A353765 (positions of 1's).

Programs

PARI

A064989(n) = { my(f=factor(n>>valuation(n,2))); for(i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f); };
A353749(n) = (eulerphi(n)*A064989(n));
A353763(n) = { my(s=sigma(n), u=A353749(s)); (u / gcd(A353749(n), u)); };

Formula

a(n) = A353750(n) / A353761(n) = A353750(n) / gcd(A353749(n), A353750(n)).