A044178 - OEIS

A044178

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

40, 89, 138, 187, 236, 280, 334, 383, 432, 481, 530, 579, 623, 677, 726, 775, 824, 873, 922, 966, 1020, 1069, 1118, 1167, 1216, 1265, 1309, 1363, 1412, 1461, 1510, 1559, 1608, 1652, 1706, 1755, 1804, 1853, 1902, 1951, 1960

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..41.

MATHEMATICA

SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 7], {5, 5}]>0, 1, 0], {n, 2000}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Dec 16 2017 *)

CROSSREFS

Sequence in context: A188335 A185718 A043414 * A044559 A092613 A005930

Adjacent sequences: A044175 A044176 A044177 * A044179 A044180 A044181

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

STATUS

approved