Numbers k such that 6 and 9 occur juxtaposed in the base-10 representation of k but not of k+1.

Terms

a(0) =69a(1) =96a(2) =169a(3) =196a(4) =269a(5) =296a(6) =369a(7) =396a(8) =469a(9) =496a(10) =569a(11) =596a(12) =669a(13) =699a(14) =769a(15) =796a(16) =869a(17) =896a(18) =969a(19) =996a(20) =1069a(21) =1096a(22) =1169a(23) =1196a(24) =1269a(25) =1296a(26) =1369a(27) =1396a(28) =1469a(29) =1496