A044508 - OEIS

A044508

Numbers n such that string 4,1 occurs in the base 6 representation of n but not of n+1.

25, 61, 97, 133, 155, 169, 205, 241, 277, 313, 349, 371, 385, 421, 457, 493, 529, 565, 587, 601, 637, 673, 709, 745, 781, 803, 817, 853, 889, 935, 961, 997, 1019, 1033, 1069, 1105, 1141, 1177, 1213, 1235, 1249, 1285, 1321, 1357, 1393, 1429, 1451, 1465, 1501

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..49.

MATHEMATICA

f[n_] := Length[StringPosition[ToString[FromDigits[IntegerDigits[n, 6]]], "41", 1]]; Select[Table[n, {n, 10000}], f[#] > 0 && f[# + 1] == 0 &] (* Vladimir Joseph Stephan Orlovsky, Jul 20 2011 *)

SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 6], {4, 1}]>0, 1, 0], {n, 1600}], {1, 0}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Mar 19 2018 *)

CROSSREFS

Cf. A044127.

Sequence in context: A241505 A090820 A044127 * A166873 A242317 A251688

Adjacent sequences: A044505 A044506 A044507 * A044509 A044510 A044511

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

STATUS

approved