A043193 - OEIS

%I #11 Aug 23 2021 01:07:13

%S 16,64,97,144,178,226,259,307,340,388,421,469,502,550,576,631,664,712,

%T 745,793,826,873,907,955,988,1036,1069,1117,1150,1198,1231,1279,1296,

%U 1393,1441,1474,1522,1555,1602,1636,1684,1717

%N Numbers k such that 1 and 7 occur juxtaposed in the base-9 representation of k but not of k-1.

%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n,9],{1,7}]>0 || SequenceCount[ IntegerDigits[n,9],{7,1}]>0,1,0],{n,1800}],{0,1}][[All,2]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Aug 03 2018 *)

%Y Cf. A007095.

%K nonn,base

%O 1,1

%A _Clark Kimberling_