A023389 a(n+1) = a(n) converted to base 9 from base 7 (written in base 10).

7, 9, 11, 13, 15, 19, 23, 29, 37, 47, 59, 93, 137, 211, 343, 729, 1513, 3133, 8077, 21435, 70255, 243939, 1085583, 5931677, 43738095, 406863821, 4668281037, 71095945599, 1434858502437, 47306783952687, 2415226651498341, 204771657238889285