A044007 - OEIS

%I #17 Aug 28 2021 02:51:15

%S 14,41,114,149,214,241,314,341,419,441,514,541,614,641,714,741,814,

%T 841,914,941,1014,1041,1114,1149,1214,1241,1314,1341,1499,1514,1541,

%U 1614,1641,1714,1741,1814,1841,1914,1941,2014,2041

%N Numbers k such that 1 and 4 occur juxtaposed in the base-10 representation of k but not of k+1.

%H Michael De Vlieger, <a href="/A044007/b044007.txt">Table of n, a(n) for n = 1..10000</a>

%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n],{1,4}]> 0 || SequenceCount[IntegerDigits[n],{4,1}]>0,1,0],{n,2100}],{1,0}] [[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jul 01 2019 *)

%K nonn,base

%O 1,1

%A _Clark Kimberling_