Write n in decimal, omit 0's, raise each digit k to k-th power and multiply.

Terms

a(0) =1a(1) =1a(2) =4a(3) =27a(4) =256a(5) =3125a(6) =46656a(7) =823543a(8) =16777216a(9) =387420489a(10) =1a(11) =1a(12) =4a(13) =27a(14) =256a(15) =3125a(16) =46656a(17) =823543a(18) =16777216a(19) =387420489a(20) =4a(21) =4a(22) =16a(23) =108a(24) =1024a(25) =12500a(26) =186624a(27) =3294172a(28) =67108864a(29) =1549681956