login
Numbers n such that string 8,8 occurs in the base 9 representation of n but not of n+1.
0

%I #11 Jan 23 2017 17:18:13

%S 80,161,242,323,404,485,566,647,728,809,890,971,1052,1133,1214,1295,

%T 1376,1457,1538,1619,1700,1781,1862,1943,2024,2105,2186,2267,2348,

%U 2429,2510,2591,2672,2753,2834,2915,2996,3077,3158

%N Numbers n such that string 8,8 occurs in the base 9 representation of n but not of n+1.

%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/NonRecursions.html">Non Recursions</a>

%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n,9],{8,8}]>0,1,0],{n,3200}],{1,0}][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jan 23 2017 *)

%Y Cf. A157597, A010734 [From _Vincenzo Librandi_, Mar 13 2009]

%K nonn,base

%O 1,1

%A _Clark Kimberling_