A044534 - OEIS

A044534

Numbers n such that string 2,1 occurs in the base 7 representation of n but not of n+1.

%I #7 Jun 24 2012 13:09:27

%S 15,64,111,113,162,211,260,309,358,407,454,456,505,554,603,652,701,

%T 783,797,799,848,897,946,995,1044,1093,1140,1142,1191,1240,1289,1338,

%U 1387,1436,1483,1485,1534,1583,1632,1681,1730,1779

%N Numbers n such that string 2,1 occurs in the base 7 representation of n but not of n+1.

%H Harvey P. Dale, <a href="/A044534/b044534.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Range[2000],MemberQ[Partition[IntegerDigits[#,7],2,1],{2,1}] && !MemberQ[Partition[IntegerDigits[#+1,7],2,1],{2,1}]&] (* _Harvey P. Dale_, Jun 24 2012 *)

%K nonn,base

%O 1,1

%A _Clark Kimberling_