Length of lists created by n substitutions k -> Range[0,1+Mod[k+1,3]] starting with {0}.

A084084

Length of lists created by n substitutions k -> Range[0,1+Mod[k+1,3]] starting with {0}.

Terms

    a(0) =1a(1) =3a(2) =9a(3) =28a(4) =86a(5) =265a(6) =816a(7) =2513a(8) =7739a(9) =23833a(10) =73396a(11) =226030a(12) =696081a(13) =2143648a(14) =6601569a(15) =20330163a(16) =62608681a(17) =192809420a(18) =593775046a(19) =1828587033a(20) =5631308624a(21) =17342153393a(22) =53406819691a(23) =164471408185a(24) =506505428836

External references