Numbers that can be written as a product of distinct repunits.

Terms

a(0) =0a(1) =1a(2) =11a(3) =111a(4) =1111a(5) =1221a(6) =11111a(7) =12221a(8) =111111a(9) =122221a(10) =123321a(11) =1111111a(12) =1222221a(13) =1233321a(14) =1356531a(15) =11111111a(16) =12222221a(17) =12333321a(18) =12344321a(19) =13566531a(20) =111111111a(21) =122222221a(22) =123333321a(23) =123444321a(24) =135666531a(25) =135787531a(26) =1111111111a(27) =1222222221