a(n) is the least k that has exactly n divisors whose arithmetic derivative is odd.

Terms

a(0) =1a(1) =2a(2) =15a(3) =6a(4) =18a(5) =405a(6) =30a(7) =162a(8) =945a(9) =90a(10) =1458a(11) =295245a(12) =210a(13) =450a(14) =25515a(15) =810a(16) =10395a(17) =455625a(18) =630a(19) =1062882a(20) =31185a(21) =7290a(22) =4050a(23) =156905298045a(24) =1890a(25) =354375a(26) =18600435a(27) =3150a(28) =280665a(30) =5670