Least k such that the k-th cyclotomic polynomial has n as a coefficient.

Terms

a(0) =4a(1) =1a(2) =165a(3) =595a(4) =1785a(5) =1785a(6) =2805a(7) =3135a(8) =6545a(9) =6545a(10) =10465a(11) =10465a(12) =10465a(13) =10465a(14) =10465a(15) =11305a(16) =11305a(17) =11305a(18) =11305a(19) =11305a(20) =11305a(21) =11305a(22) =15015a(23) =11305a(24) =20615a(25) =17255a(26) =20615a(27) =20615a(28) =26565a(29) =26565