Index of 6^n within the sequence of the numbers of the form 6^i*9^j.

Terms

a(0) =1a(1) =2a(2) =4a(3) =7a(4) =11a(5) =16a(6) =21a(7) =27a(8) =34a(9) =42a(10) =51a(11) =60a(12) =70a(13) =81a(14) =93a(15) =106a(16) =120a(17) =134a(18) =149a(19) =165a(20) =182a(21) =200a(22) =218a(23) =237a(24) =257a(25) =278a(26) =300a(27) =323a(28) =346a(29) =370