The OEIS is supported by the many generous donors to the OEIS Foundation.
%I #13 Apr 11 2022 11:20:10
%S 17,71,117,179,217,271,317,371,417,471,517,571,617,671,719,771,817,
%T 871,917,971,1017,1071,1117,1179,1217,1271,1317,1371,1417,1471,1517,
%U 1571,1617,1671,1799,1817,1871,1917,1971,2017,2071
%N Numbers k such that 1 and 7 occur juxtaposed in the base-10 representation of k but not of k+1.
%H Michael De Vlieger, <a href="/A044010/b044010.txt">Table of n, a(n) for n = 1..10000</a>
%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n],{1,7}]>0 || SequenceCount[ IntegerDigits[n],{7,1}]>0,1,0],{n,2100}],{1,0}][[All,1]] (* _Harvey P. Dale_, Apr 11 2022 *)
%K nonn,base
%O 1,1
%A _Clark Kimberling_