a(n) = (10*n + 7)^6.

Terms

a(0) =117649a(1) =24137569a(2) =387420489a(3) =2565726409a(4) =10779215329a(5) =34296447249a(6) =90458382169a(7) =208422380089a(8) =433626201009a(9) =832972004929