A044317 Numbers n such that string 7,3 occurs in the base 9 representation of n but not of n-1.

66, 147, 228, 309, 390, 471, 552, 594, 633, 714, 795, 876, 957, 1038, 1119, 1200, 1281, 1323, 1362, 1443, 1524, 1605, 1686, 1767, 1848, 1929, 2010, 2052, 2091, 2172, 2253, 2334, 2415, 2496, 2577, 2658, 2739, 2781, 2820

Offset

1,1

Links

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

Mathematica

Select[Range[3000], MemberQ[Partition[IntegerDigits[#, 9], 2, 1], {7, 3}] && !MemberQ[Partition[IntegerDigits[#-1, 9], 2, 1], {7, 3}]&] (* Harvey P. Dale, Sep 16 2011 *)
SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 9], {7, 3}]>0, 1, 0], {n, 3000}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jan 28 2020 *)

Crossrefs

Sequence in context: A174929 A072430 A278126 * A044698 A122125 A278783

Adjacent sequences: A044314 A044315 A044316 * A044318 A044319 A044320

Keyword

nonn,base

Author

Clark Kimberling

Status

approved