# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a044438 Showing 1-1 of 1 %I A044438 #7 Mar 19 2018 18:23:01 %S A044438 5,17,23,32,53,59,71,77,86,98,104,113,161,167,179,185,194,215,221,233, %T A044438 239,248,260,266,275,296,302,314,320,329,341,347,356,485,491,503,509, %U A044438 518,539,545,557,563,572,584,590,599,647,653 %N A044438 Numbers n such that string 1,2 occurs in the base 3 representation of n but not of n+1. %t A044438 SequencePosition[Table[If[SequenceCount[IntegerDigits[n,3],{1,2}]>0,1,0],{n,700}],{1,0}][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Mar 19 2018 *) %K A044438 nonn,base %O A044438 1,1 %A A044438 _Clark Kimberling_ # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE