271500domain: NAppears in sequencesG.f.: A(x) = exp( Sum_{n>=1} A179307(n)*x^n/n ), where A179307(n) = Sum_{d|n} C(n,d)*sigma(d)*sigma(n/d).at n=14A179306Number of equivalence classes of S_n under transformations of positionally and numerically adjacent elements of the form abc <--> acb <--> bac <--> cba, where a<b<c.at n=9A212433