Position of n-th 9 in A031324.

Terms

a(0) =15a(1) =28a(2) =33a(3) =49a(4) =76a(5) =79a(6) =95a(7) =108a(8) =115a(9) =130a(10) =139a(11) =154a(12) =160a(13) =166a(14) =190a(15) =194a(16) =200a(17) =218a(18) =231a(19) =235a(20) =251a(21) =263a(22) =271a(23) =288a(24) =295a(25) =296a(26) =303a(27) =321a(28) =350a(29) =356