A044076 - OEIS

A044076

Numbers k such that string 3,3 occurs in the base 4 representation of k but not of k-1.

15, 31, 47, 60, 79, 95, 111, 124, 143, 159, 175, 188, 207, 223, 239, 271, 287, 303, 316, 335, 351, 367, 380, 399, 415, 431, 444, 463, 479, 495, 527, 543, 559, 572, 591, 607, 623, 636, 655, 671, 687, 700, 719, 735, 751, 783, 799, 815, 828, 847, 863, 879, 892, 911, 927

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

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

MATHEMATICA

A044076Q[k_] := StringContainsQ[IntegerString[k, 4], "33"] && StringFreeQ[IntegerString[k - 1, 4], "33"];

Select[Range[2000], A044076Q] (* Paolo Xausa, Sep 24 2025 *)

CROSSREFS

Cf. A007090.

Sequence in context: A023719 A031467 A045063 * A319282 A125169 A044457

Adjacent sequences: A044073 A044074 A044075 * A044077 A044078 A044079