A043209 Numbers k such that 4 and 8 occur juxtaposed in the base-9 representation of k but not of k-1.

44, 76, 125, 157, 206, 238, 287, 319, 368, 396, 449, 481, 530, 562, 611, 643, 684, 724, 773, 805, 854, 886, 935, 967, 1016, 1048, 1097, 1125, 1178, 1210, 1259, 1291, 1340, 1372, 1413, 1453, 1502, 1534, 1583, 1615, 1664, 1696

Offset

1,1

Links

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

Mathematica

SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 9], {4, 8}]>0||SequenceCount[ IntegerDigits[n, 9], {8, 4}]>0, 1, 0], {n, 2000}], {0, 1}][[All, 2]] (* Harvey P. Dale, Dec 12 2022 *)

Crossrefs

Cf. A007095.

Sequence in context: A049103 A074172 A039386 * A043989 A050272 A260201

Adjacent sequences: A043206 A043207 A043208 * A043210 A043211 A043212

Keyword

nonn,base

Author

Clark Kimberling

Status

approved