A044171 - OEIS

A044171

Numbers n such that string 4,5 occurs in the base 7 representation of n but not of n-1.

33, 82, 131, 180, 229, 231, 278, 327, 376, 425, 474, 523, 572, 574, 621, 670, 719, 768, 817, 866, 915, 917, 964, 1013, 1062, 1111, 1160, 1209, 1258, 1260, 1307, 1356, 1405, 1454, 1503, 1552, 1601, 1603, 1617, 1699, 1748, 1797

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..42.

MATHEMATICA

SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 7], {4, 5}]>0, 1, 0], {n, 2000}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Feb 14 2017 *)

CROSSREFS

Sequence in context: A138866 A001987 A094846 * A044552 A045939 A056809

Adjacent sequences: A044168 A044169 A044170 * A044172 A044173 A044174

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

STATUS

approved