a(n) = Sum_{k <= 10^n} cototient(k), where cototient is A051953.

A064016

a(n) = Sum_{k <= 10^n} cototient(k), where cototient is A051953.

Terms

    a(0) =0a(1) =23a(2) =2006a(3) =196308a(4) =19607514a(5) =1960399246a(6) =196036947608

External references