a(n) is the smallest k (powers of 10 excluded) such that sod(k), sod(k^2),..., sod(k^n) is an arithmetic progression, where sod(m) = A007953(m) is the sum of the digits of m.

A258722

a(n) is the smallest k (powers of 10 excluded) such that sod(k), sod(k^2),..., sod(k^n) is an arithmetic progression, where sod(m) = A007953(m) is the sum of the digits of m.

Terms

    a(0) =4a(1) =4a(2) =16a(3) =16a(4) =16a(5) =7972a(6) =7972a(7) =134242a(8) =59716233a(9) =1844284813a(10) =77298251764

External references