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A044147
Numbers n such that string 1,2 occurs in the base 7 representation of n but not of n-1.
0
9, 58, 63, 107, 156, 205, 254, 303, 352, 401, 406, 441, 499, 548, 597, 646, 695, 744, 749, 793, 842, 891, 940, 989, 1038, 1087, 1092, 1136, 1185, 1234, 1283, 1332, 1381, 1430, 1435, 1479, 1528, 1577, 1626, 1675, 1724, 1773
OFFSET
1,1
MATHEMATICA
SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 7], {1, 2}]>0, 1, 0], {n, 2000}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Dec 06 2018 *)
CROSSREFS
Sequence in context: A197673 A012089 A343133 * A044528 A027174 A304370
KEYWORD
nonn,base
STATUS
approved