A044153 Numbers n such that string 2,1 occurs in the base 7 representation of n but not of n-1.

15, 64, 105, 113, 162, 211, 260, 309, 358, 407, 448, 456, 505, 554, 603, 652, 701, 735, 791, 799, 848, 897, 946, 995, 1044, 1093, 1134, 1142, 1191, 1240, 1289, 1338, 1387, 1436, 1477, 1485, 1534, 1583, 1632, 1681, 1730, 1779

Offset

1,1

Links

Table of n, a(n) for n=1..42.

Mathematica

SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 7], {2, 1}]>0, 1, 0], {n, 2000}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Oct 19 2018 *)

Crossrefs

Sequence in context: A138104 A152099 A119496 * A044534 A063483 A320555

Adjacent sequences: A044150 A044151 A044152 * A044154 A044155 A044156

Keyword

nonn,base

Author

Clark Kimberling

Status

approved