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A043194
Numbers k such that 1 and 8 occur juxtaposed in the base-9 representation of k but not of k-1.
0
17, 73, 98, 153, 179, 235, 260, 316, 341, 397, 422, 478, 503, 559, 584, 640, 657, 721, 746, 802, 827, 882, 908, 964, 989, 1045, 1070, 1126, 1151, 1207, 1232, 1288, 1313, 1369, 1377, 1475, 1531, 1556, 1611, 1637, 1693, 1718
OFFSET
1,1
MATHEMATICA
SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 9], {1, 8}]> 0 || SequenceCount[IntegerDigits[n, 9], {8, 1}]>0, 1, 0], {n, 2000}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Nov 23 2019 *)
CROSSREFS
Cf. A007095.
Sequence in context: A144245 A307718 A139919 * A043974 A141972 A161735
KEYWORD
nonn,base
STATUS
approved