A043219 Numbers k such that 0 and 4 occur juxtaposed in the base-10 representation of k but not of k-1.

40, 104, 140, 204, 240, 304, 340, 400, 440, 504, 540, 604, 640, 704, 740, 804, 840, 904, 940, 1004, 1040, 1104, 1140, 1204, 1240, 1304, 1340, 1400, 1440, 1504, 1540, 1604, 1640, 1704, 1740, 1804, 1840, 1904, 1940, 2004, 2040

Offset

1,1

Links

Table of n, a(n) for n=1..41.

Mathematica

SequencePosition[Table[If[SequenceCount[IntegerDigits[n], {0, 4}]>0||SequenceCount[ IntegerDigits[ n], {4, 0}]>0, 1, 0], {n, 3000}], {0, 1}][[;; , 2]] (* Harvey P. Dale, Aug 16 2024 *)

Crossrefs

Sequence in context: A235271 A033832 A235017 * A039396 A043999 A044227

Adjacent sequences: A043216 A043217 A043218 * A043220 A043221 A043222

Keyword

nonn,base,changed

Author

Clark Kimberling

Status

approved