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A044153
Numbers n such that string 2,1 occurs in the base 7 representation of n but not of n-1.
0
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
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
KEYWORD
nonn,base
STATUS
approved