Base-10 lunar factorials: a(n) = (lunar) Product_{i=1..n} i.

Terms

a(0) =9a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =1a(9) =1a(10) =10a(11) =110a(12) =1110a(13) =11110a(14) =111110a(15) =1111110a(16) =11111110a(17) =111111110a(18) =1111111110a(19) =11111111110a(20) =111111111100