44921domain: NAppears in sequencesn is equal to the number of 4s in all numbers <= n written in base 6.at n=1A014892Expansion of chi(x^2) / phi(x) in powers of x where phi(), chi() are Ramanujan theta functions.at n=24A246712Number of quaternary steady words of length n (with respect to the permutations of symbols).at n=49A357250