a(n) = (30^n - 1)/29.A218733a(n) = (30^n - 1)/29.Terms a(0) =0a(1) =1a(2) =31a(3) =931a(4) =27931a(5) =837931a(6) =25137931a(7) =754137931a(8) =22624137931a(9) =678724137931External referencesoeis: A218733