A043196 Numbers k such that 2 and 4 occur juxtaposed in the base-9 representation of k but not of k-1.

22, 38, 103, 119, 184, 198, 265, 281, 342, 362, 427, 443, 508, 524, 589, 605, 670, 686, 751, 767, 832, 848, 913, 927, 994, 1010, 1071, 1091, 1156, 1172, 1237, 1253, 1318, 1334, 1399, 1415, 1480, 1496, 1561, 1577, 1642, 1656

Offset

1,1

Links

Table of n, a(n) for n=1..42.

Mathematica

Transpose[SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 9], {2, 4}]>0||SequenceCount[IntegerDigits[n, 9], {4, 2}]>0, 1, 0], {n, 2000}], {0, 1}]][[2]] (* The program uses the SequencePosition and SequenceCount functions from Mathematica version 10.1 *) (* Harvey P. Dale, Apr 08 2015 *)

Crossrefs

Cf. A007095.

Sequence in context: A057836 A078612 A039373 * A043976 A131196 A075217

Adjacent sequences: A043193 A043194 A043195 * A043197 A043198 A043199

Keyword

nonn,base

Author

Clark Kimberling

Status

approved