A044260 Numbers k such that string 1,0 occurs in the base 9 representation of k but not of k-1.

9, 81, 171, 252, 333, 414, 495, 576, 657, 729, 900, 981, 1062, 1143, 1224, 1305, 1386, 1467, 1539, 1629, 1710, 1791, 1872, 1953, 2034, 2115, 2196, 2268, 2358, 2439, 2520, 2601, 2682, 2763, 2844, 2925, 2997, 3087, 3168

Offset

1,1

Links

Paolo Xausa, Table of n, a(n) for n = 1..10000

Mathematica

A044260Q[k_] := StringContainsQ[IntegerString[k, 9], "10"] && StringFreeQ[IntegerString[k - 1, 9], "10"];
Select[Range[5000], A044260Q] (* Paolo Xausa, Sep 02 2025 *)
SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 9], {1, 0}]>0, 1, 0], {n, 3200}], {0, 1}][[;; , 2]] (* Harvey P. Dale, Mar 23 2026 *)

Crossrefs

Sequence in context: A207510 A208104 A207725 * A208109 A208841 A207489

Adjacent sequences: A044257 A044258 A044259 * A044261 A044262 A044263

Keyword

nonn,base

Author

Clark Kimberling

Status

approved