A044770 - OEIS

A044770

Numbers n such that string 5,7 occurs in the base 10 representation of n but not of n+1.

57, 157, 257, 357, 457, 557, 579, 657, 757, 857, 957, 1057, 1157, 1257, 1357, 1457, 1557, 1579, 1657, 1757, 1857, 1957, 2057, 2157, 2257, 2357, 2457, 2557, 2579, 2657, 2757, 2857, 2957, 3057, 3157, 3257, 3357, 3457, 3557

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..39.

MATHEMATICA

SequencePosition[Table[If[SequenceCount[IntegerDigits[n], {5, 7}]>0, 1, 0], {n, 4000}], {1, 0}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 14 2019 *)

CROSSREFS

Sequence in context: A250606 A356423 A044389 * A008877 A338078 A336191

Adjacent sequences: A044767 A044768 A044769 * A044771 A044772 A044773

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

STATUS

approved