Algebraic cofactor of n-th repunit A002275(n).

Terms

a(0) =1a(1) =1a(2) =1a(3) =11a(4) =1a(5) =1221a(6) =1a(7) =1111a(8) =333a(9) =122221a(10) =1a(11) =11222211a(12) =1a(13) =12222221a(14) =1233321a(15) =11111111a(16) =1a(17) =111222222111a(18) =1a(19) =112222222211a(20) =123333321a(22) =1a(24) =11111a(26) =333333333a(28) =1a(30) =1