A044167 Numbers k such that string 4,1 occurs in the base 7 representation of k but not of k-1.

29, 78, 127, 176, 203, 225, 274, 323, 372, 421, 470, 519, 546, 568, 617, 666, 715, 764, 813, 862, 889, 911, 960, 1009, 1058, 1107, 1156, 1205, 1232, 1254, 1303, 1352, 1401, 1421, 1499, 1548, 1575, 1597, 1646, 1695, 1744, 1793, 1842, 1891, 1918, 1940, 1989, 2038, 2087

Offset

1,1

Links

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

Mathematica

A044167Q[k_] := StringContainsQ[IntegerString[k, 7], "41"] && StringFreeQ[IntegerString[k - 1, 7], "41"];
Select[Range[5000], A044167Q] (* Paolo Xausa, Sep 10 2025 *)

Crossrefs

Cf. A007093.

Sequence in context: A263534 A273360 A176185 * A044548 A144584 A039461

Adjacent sequences: A044164 A044165 A044166 * A044168 A044169 A044170

Keyword

nonn,base

Author

Clark Kimberling

Extensions

More terms from Paolo Xausa, Sep 10 2025

Status

approved