91625968982domain: NAppears in sequencesa(n) = (4^n + 2)/3.at n=19A047849Generalized multiplicative Jacobsthal sequence.at n=38A087464Second trisection of A024494.at n=12A132397a(0)=1, a(n)= 2+2^n/6+4*(-1)^n/3, n>0.at n=39A173197