The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A044159 Numbers n such that string 3,0 occurs in the base 7 representation of n but not of n-1. 0
 21, 70, 119, 147, 168, 217, 266, 315, 364, 413, 462, 490, 511, 560, 609, 658, 707, 756, 805, 833, 854, 903, 952, 1001, 1029, 1099, 1148, 1176, 1197, 1246, 1295, 1344, 1393, 1442, 1491, 1519, 1540, 1589, 1638, 1687, 1736, 1785 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS MATHEMATICA Select[Range[2000], MemberQ[Partition[IntegerDigits[#, 7], 2, 1], {3, 0}] && !MemberQ[Partition[IntegerDigits[#-1, 7], 2, 1], {3, 0}]&] (* or *) Flatten[ Position[Partition[If[MemberQ[Partition[IntegerDigits[#, 7], 2, 1], {3, 0}], 1, 0]&/@Range[2000], 2, 1], {0, 1}]]+1 (* Harvey P. Dale, Aug 21 2013 *) SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 7], {3, 0}]>0, 1, 0], {n, 1800}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Sep 15 2019 *) CROSSREFS Sequence in context: A155492 A201066 A200931 * A044540 A195026 A296035 Adjacent sequences:  A044156 A044157 A044158 * A044160 A044161 A044162 KEYWORD nonn,base AUTHOR STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified July 29 04:15 EDT 2021. Contains 346340 sequences. (Running on oeis4.)