login
A328925
a(n) = A002322(n)/A118106(n); write n = Product_{i=1..t} p_i^e_i, then a(n) = A002322(n)/(lcm_{1<=i,j<=t,i!=j} ord(p_i,p_j^e_j)), where ord(a,r) is the multiplicative order of a modulo r, and A002322 is the Carmichael lambda (usually written as psi).
2
1, 1, 2, 2, 4, 1, 6, 2, 6, 1, 10, 1, 12, 2, 1, 4, 16, 1, 18, 1, 1, 1, 22, 1, 20, 1, 18, 1, 28, 1, 30, 8, 1, 2, 1, 1, 36, 1, 4, 1, 40, 1, 42, 1, 1, 2, 46, 1, 42, 1, 1, 1, 52, 1, 4, 1, 1, 1, 58, 1, 60, 6, 1, 16, 3, 1, 66, 2, 1, 1, 70, 1, 72, 1, 1, 1, 1, 1, 78, 1, 54, 2, 82, 1, 1, 3, 1
OFFSET
1,3
COMMENTS
It is easy to see that A118106(n) divides psi(n) = A002322(n).
If n = p^e for prime p, then A118106(p^e) = 1, so a(p^e) = A002322(p^e). The other n's such that a(n) > 1 are listed in A329062.
EXAMPLE
A002322(14) = 6, while A118106(14) = 3, so a(14) = 2.
PROG
(PARI) a(n) = A002322(n)/A118106(n) \\ See A002322 and A118106 for their programs
CROSSREFS
Cf. A002322, A118106, A328926 (indices of 1), A329062.
Sequence in context: A069922 A072211 A360825 * A299020 A343505 A365687
KEYWORD
nonn
AUTHOR
Jianing Song, Oct 31 2019
STATUS
approved