cp's OEIS Frontend

First differs from its subsequence A383697 at n = 21.

All the terms are nonsquarefree numbers (A013929), since A322857(k) = k if k is a squarefree number (A005117).

If an exponential abundant number (A129575) is exponentially squarefree (A209061), then it is in this sequence. Terms of this sequence that are not exponentially squarefree are a(21) = 22500, a(77) = 86436, a(140) = 157500, etc..

The least odd term is a(202273) = 225450225, and the least term that is coprime to 6 is a(1.002..*10^18) = 1117347505588495206025.

The asymptotic density of this sequence is Sum_{n>=1} f(A383694(n)) = 0.00089722..., where f(n) = (6/(Pi^2*n))*Product_{prime p|n}(p/(p+1)).

Subsequence of A383694 and first differs from it at n = 11.

The least odd term is a(1345) = 225450225, and the least term that is coprime to 6 is 1117347505588495206025.

For squarefree numbers k, essigma(k) = k, where essigma is the sum of exponential squarefree exponential divisors function (A361174). Thus, if m is a term (essigma(m) > 2*m) and k is a squarefree number coprime to m, then essigma(k*m) = essigma(k) * essigma(m) = k * essigma(m) > 2*k*m, so k*m is an exponential squarefree exponential abundant number. Therefore, the sequence of exponential squarefree exponential abundant numbers (A383697) can be generated from this sequence by multiplying with coprime squarefree numbers.