A044316 Numbers n such that string 7,2 occurs in the base 9 representation of n but not of n-1.

65, 146, 227, 308, 389, 470, 551, 585, 632, 713, 794, 875, 956, 1037, 1118, 1199, 1280, 1314, 1361, 1442, 1523, 1604, 1685, 1766, 1847, 1928, 2009, 2043, 2090, 2171, 2252, 2333, 2414, 2495, 2576, 2657, 2738, 2772, 2819

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

s72Q[n_]:=MemberQ[Partition[IntegerDigits[n, 9], 2, 1], {7, 2}]; Flatten[ Position[ Partition[Boole[Array[s72Q, 3000]], 2, 1], {0, 1}]]+1 (* Harvey P. Dale, Jan 13 2015 *)
SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 9], {7, 2}]>0, 1, 0], {n, 3000}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 27 2019 *)

Crossrefs

Sequence in context: A226926 A345700 A121944 * A044697 A350209 A326157

Adjacent sequences: A044313 A044314 A044315 * A044317 A044318 A044319

Keyword

nonn,base

Author

Clark Kimberling

Status

approved