a(n) = Sum_{k=1..n} tau(gcd(k,n)^gcd(k,n)), where tau(n) is the number of divisors of n.

Terms

a(0) =1a(1) =4a(2) =6a(3) =14a(4) =10a(5) =61a(6) =14a(7) =44a(8) =33a(9) =143a(10) =22a(11) =410a(12) =26a(13) =257a(14) =292a(15) =128a(16) =34a(17) =852a(18) =38a(19) =1050a(20) =536a(21) =581a(22) =46a(23) =2352a(24) =95a(25) =791a(26) =162a(27) =1978a(28) =58a(29) =30545