a(n) = n + [n^2 if n is odd or n^3 if n is even].

Terms

a(0) =2a(1) =10a(2) =12a(3) =68a(4) =30a(5) =222a(6) =56a(7) =520a(8) =90a(9) =1010a(10) =132a(11) =1740a(12) =182a(13) =2758a(14) =240a(15) =4112a(16) =306a(17) =5850a(18) =380a(19) =8020a(20) =462a(21) =10670a(22) =552a(23) =13848a(24) =650a(25) =17602a(26) =756a(27) =21980a(28) =870a(29) =27030