Composite numbers whose multiplicative digital root is 7.

Terms

a(0) =117a(1) =171a(2) =711a(3) =1711a(4) =7111a(5) =11711a(6) =17111a(7) =71111a(8) =111117a(9) =111171a(10) =111711a(11) =117111a(12) =171111a(13) =711111a(14) =1111117a(15) =1111171a(16) =1711111a(17) =7111111a(18) =11111711a(19) =11117111a(20) =11171111a(21) =11711111a(22) =17111111a(23) =111111117a(24) =111111171a(25) =111111711a(26) =111117111a(27) =111171111a(28) =111711111a(29) =117111111