Powers of 6: a(n) = 6^n.

Terms

a(0) =1a(1) =6a(2) =36a(3) =216a(4) =1296a(5) =7776a(6) =46656a(7) =279936a(8) =1679616a(9) =10077696a(10) =60466176a(11) =362797056a(12) =2176782336a(13) =13060694016a(14) =78364164096a(15) =470184984576