a(n) = floor(n!^(1/3)).

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =4a(6) =8a(7) =17a(8) =34a(9) =71a(10) =153a(11) =341a(12) =782a(13) =1839a(14) =4434a(15) =10935a(16) =27555a(17) =70852a(18) =185686a(19) =495486a(20) =1344956a(21) =3710632a(22) =10397338a(23) =29568648a(24) =85290741a(25) =249391641a(26) =738821756a(27) =2216465268a(28) =6730493989a(29) =20678209929