Numbers n such that string 6,8 occurs in the base 10 representation of n but not of n-1.

Terms

a(0) =68a(1) =168a(2) =268a(3) =368a(4) =468a(5) =568a(6) =668a(7) =680a(8) =768a(9) =868a(10) =968a(11) =1068a(12) =1168a(13) =1268a(14) =1368a(15) =1468a(16) =1568a(17) =1668a(18) =1680a(19) =1768a(20) =1868a(21) =1968a(22) =2068a(23) =2168a(24) =2268a(25) =2368a(26) =2468a(27) =2568a(28) =2668a(29) =2680