%I #7 Jan 28 2024 13:35:38
%S 40,89,138,187,236,286,334,383,432,481,530,579,629,677,726,775,824,
%T 873,922,972,1020,1069,1118,1167,1216,1265,1315,1363,1412,1461,1510,
%U 1559,1608,1658,1706,1755,1804,1853,1902,1951,2008
%N Numbers n such that string 5,5 occurs in the base 7 representation of n but not of n+1.
%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n,7],{5,5}]>0,1,0],{n,2100}],{1,0}][[;;,1]] (* _Harvey P. Dale_, Jan 28 2024 *)
%K nonn,base
%O 1,1
%A _Clark Kimberling_
|