A043249 Numbers k such that 4 and 8 occur juxtaposed in the base-10 representation of k but not of k-1.

48, 84, 148, 184, 248, 284, 348, 384, 448, 480, 548, 584, 648, 684, 748, 784, 840, 884, 948, 984, 1048, 1084, 1148, 1184, 1248, 1284, 1348, 1384, 1448, 1480, 1548, 1584, 1648, 1684, 1748, 1784, 1840, 1884, 1948, 1984, 2048

Offset

1,1

Links

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

Mathematica

SequencePosition[Table[If[SequenceCount[IntegerDigits[n], {4, 8}]>0 || SequenceCount[IntegerDigits[n], {8, 4}]>0, 1, 0], {n, 2100}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 25 2020 *)

Crossrefs

Sequence in context: A260501 A260494 A039426 * A044029 A333814 A062902

Adjacent sequences: A043246 A043247 A043248 * A043250 A043251 A043252

Keyword

nonn,base

Author

Clark Kimberling

Status

approved