A044356 Numbers k such that the string 2,4 occurs in the base 10 representation of k but not of k-1.

24, 124, 224, 240, 324, 424, 524, 624, 724, 824, 924, 1024, 1124, 1224, 1240, 1324, 1424, 1524, 1624, 1724, 1824, 1924, 2024, 2124, 2224, 2240, 2324, 2400, 2524, 2624, 2724, 2824, 2924, 3024, 3124, 3224, 3240, 3324, 3424, 3524, 3624, 3724, 3824, 3924, 4024, 4124, 4224

Offset

1,1

Links

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

Mathematica

A044356Q[k_] := StringContainsQ[IntegerString[k], "24"] && StringFreeQ[IntegerString[k - 1], "24"];
Select[Range[5000], A044356Q] (* Paolo Xausa, Nov 03 2025 *)

Crossrefs

Sequence in context: A042120 A002980 A244794 * A044737 A305159 A326367

Adjacent sequences: A044353 A044354 A044355 * A044357 A044358 A044359

Keyword

nonn,base

Author

Clark Kimberling

Extensions

More terms from Paolo Xausa, Nov 03 2025

Status

approved