A044020 Numbers k such that 3 and 4 occur juxtaposed in the base-10 representation of k but not of k+1.

34, 43, 134, 143, 234, 243, 334, 349, 439, 443, 534, 543, 634, 643, 734, 743, 834, 843, 934, 943, 1034, 1043, 1134, 1143, 1234, 1243, 1334, 1349, 1439, 1443, 1534, 1543, 1634, 1643, 1734, 1743, 1834, 1843, 1934, 1943, 2034

Offset

1,1

Links

Table of n, a(n) for n=1..41.

Mathematica

SequencePosition[Table[If[SequenceCount[IntegerDigits[n], {3, 4}]>0 || SequenceCount[ IntegerDigits[n], {4, 3}]>0, 1, 0], {n, 2500}], {1, 0}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Dec 09 2017 *)

Crossrefs

Sequence in context: A232581 A039417 A043240 * A217276 A076772 A359331

Adjacent sequences: A044017 A044018 A044019 * A044021 A044022 A044023

Keyword

nonn,base

Author

Clark Kimberling

Status

approved