Sum of the divisors of 8^n-1.

Terms

a(0) =8a(1) =104a(2) =592a(3) =8736a(4) =38912a(5) =473600a(6) =2466048a(7) =38054016a(8) =155493536a(9) =2015330304a(10) =10359014400a(11) =166290432000a(12) =636328345600