login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A044543
Numbers n such that string 3,3 occurs in the base 7 representation of n but not of n+1.
0
24, 73, 122, 174, 220, 269, 318, 367, 416, 465, 517, 563, 612, 661, 710, 759, 808, 860, 906, 955, 1004, 1053, 1102, 1151, 1224, 1249, 1298, 1347, 1396, 1445, 1494, 1546, 1592, 1641, 1690, 1739, 1788, 1837, 1889, 1935, 1984
OFFSET
1,1
MATHEMATICA
Transpose[SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 7], {3, 3}]>0, 1, 0], {n, 3000}], {1, 0}]][[1]] (* The program uses the SequencePosition and SequenceCount functions from Mathematica version 10 *) (* Harvey P. Dale, May 18 2015 *)
CROSSREFS
Sequence in context: A042128 A043406 A044162 * A161587 A042130 A042132
KEYWORD
nonn,base
STATUS
approved