Numbers k such that string 2,3 occurs in the base 7 representation of k but not of k-1.

Terms

a(0) =17a(1) =66a(2) =115a(3) =119a(4) =164a(5) =213a(6) =262a(7) =311a(8) =360a(9) =409a(10) =458a(11) =462a(12) =507a(13) =556a(14) =605a(15) =654a(16) =703a(17) =752a(18) =801a(19) =805a(20) =833a(21) =899a(22) =948a(23) =997a(24) =1046a(25) =1095a(26) =1144a(27) =1148a(28) =1193a(29) =1242