n-th cyclotomic polynomial has more terms then the largest prime factor of n.
1, 15, 21, 30, 33, 35, 39, 42, 45, 51, 55, 57, 60, 63, 65, 66, 69, 70, 75, 77, 78, 84, 85
1 seqfan posts
Sun Jan 18 14:20:20 CET 2009 [seqfan] count of terms in cyclotomic polynomial