A044155 Numbers k such that string 2,3 occurs in the base 7 representation of k but not of k-1.

17, 66, 115, 119, 164, 213, 262, 311, 360, 409, 458, 462, 507, 556, 605, 654, 703, 752, 801, 805, 833, 899, 948, 997, 1046, 1095, 1144, 1148, 1193, 1242, 1291, 1340, 1389, 1438, 1487, 1491, 1536, 1585, 1634, 1683, 1732, 1781, 1830, 1834, 1879, 1928, 1977, 2026, 2075

Offset

1,1

Links

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

Mathematica

A044155Q[k_] := StringContainsQ[IntegerString[k, 7], "23"] && StringFreeQ[IntegerString[k - 1, 7], "23"];
Select[Range[5000], A044155Q] (* Paolo Xausa, Sep 10 2025 *)

Crossrefs

Cf. A007093.

Sequence in context: A360818 A216143 A082614 * A044536 A115295 A065011

Adjacent sequences: A044152 A044153 A044154 * A044156 A044157 A044158

Keyword

nonn,base

Author

Clark Kimberling

Extensions

More terms from Paolo Xausa, Sep 10 2025

Status

approved