%I #11 Aug 26 2021 03:17:52

%S 13,41,77,111,141,169,205,233,269,297,335,361,397,425,461,489,525,553,

%T 589,623,653,681,717,745,781,809,895,909,937,973,1001,1037,1065,1101,

%U 1135,1165,1193,1229,1257,1293,1321,1359,1385

%N Numbers k such that 1 and 5 occur juxtaposed in the base-8 representation of k but not of k+1.

%t Transpose[SequencePosition[Table[If[SequenceCount[IntegerDigits[n,8],{1,5}]>0||SequenceCount[IntegerDigits[n,8],{5,1}]>0,1,0],{n,1500}],{1,0}]][[1]] (* The program uses the SequencePosition and SequenceCount functions from Mathematica version 10 *) (* _Harvey P. Dale_, Jun 09 2016 *)

%Y Cf. A007094.

%K nonn,base

%O 1,1

%A _Clark Kimberling_