A044457 Numbers n such that string 3,3 occurs in the base 4 representation of n but not of n+1.

15, 31, 47, 63, 79, 95, 111, 127, 143, 159, 175, 191, 207, 223, 255, 271, 287, 303, 319, 335, 351, 367, 383, 399, 415, 431, 447, 463, 479, 511, 527, 543, 559, 575, 591, 607, 623, 639, 655, 671, 687, 703, 719, 735, 767, 783, 799

Offset

1,1

Links

Table of n, a(n) for n=1..47.

Mathematica

Select[Range[800], MemberQ[Partition[IntegerDigits[#, 4], 2, 1], {3, 3}] && !MemberQ[Partition[IntegerDigits[#+1, 4], 2, 1], {3, 3}]&] (* Harvey P. Dale, Dec 11 2011 *)
SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 4], {3, 3}]>0, 1, 0], {n, 800}], {1, 0}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 30 2019 *)

Crossrefs

Sequence in context: A044076 A319282 A125169 * A249452 A132757 A045135

Adjacent sequences: A044454 A044455 A044456 * A044458 A044459 A044460

Keyword

nonn,base

Author

Clark Kimberling

Status

approved