login
A043193
Numbers k such that 1 and 7 occur juxtaposed in the base-9 representation of k but not of k-1.
0
16, 64, 97, 144, 178, 226, 259, 307, 340, 388, 421, 469, 502, 550, 576, 631, 664, 712, 745, 793, 826, 873, 907, 955, 988, 1036, 1069, 1117, 1150, 1198, 1231, 1279, 1296, 1393, 1441, 1474, 1522, 1555, 1602, 1636, 1684, 1717
OFFSET
1,1
MATHEMATICA
SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 9], {1, 7}]>0 || SequenceCount[ IntegerDigits[n, 9], {7, 1}]>0, 1, 0], {n, 1800}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 03 2018 *)
CROSSREFS
Cf. A007095.
Sequence in context: A324880 A304476 A129588 * A043973 A153262 A316301
KEYWORD
nonn,base
STATUS
approved