397468domain: NAppears in sequencesG.f.: A(x) = ...o x/(1-x^8) o x/(1-x^4) o x/(1-x^2) o x/(1-x), composition of functions x/(1 - x^{2^n}) for n=...,3,2,1,0.at n=15A136753Numbers k such that k^(2^13) + 1 is prime (a generalized Fermat prime).at n=27A226528