11544312984domain: NAppears in sequencesG.f.: 7/(3 + 4*sqrt(1-28*x)).at n=8A130979Expansion of c(7*x^2)/(1 - x*c(7*x^2)), where c(x) is the g.f. of A000108.at n=16A132374Number of length 2n n-ary words that can be built by repeatedly inserting doublets into the initially empty word.at n=8A294491