a(n) = Product{k>=0} (1 + floor(n/3^k)).

Terms

a(0) =1a(1) =2a(2) =3a(3) =8a(4) =10a(5) =12a(6) =21a(7) =24a(8) =27a(9) =80a(10) =88a(11) =96a(12) =130a(13) =140a(14) =150a(15) =192a(16) =204a(17) =216a(18) =399a(19) =420a(20) =441a(21) =528a(22) =552a(23) =576a(24) =675a(25) =702a(26) =729a(27) =2240a(28) =2320a(29) =2400