A044031 Numbers k such that 5 and 6 occur juxtaposed in the base-10 representation of k but not of k+1.

56, 65, 156, 165, 256, 265, 356, 365, 456, 465, 556, 569, 659, 665, 756, 765, 856, 865, 956, 965, 1056, 1065, 1156, 1165, 1256, 1265, 1356, 1365, 1456, 1465, 1556, 1569, 1659, 1665, 1756, 1765, 1856, 1865, 1956, 1965, 2056

Offset

1,1

Links

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

Mathematica

SequencePosition[Table[If[SequenceCount[IntegerDigits[n], {5, 6}]>0 || SequenceCount[ IntegerDigits[n], {6, 5}]>0, 1, 0], {n, 2100}], {1, 0}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Nov 15 2020 *)

Crossrefs

Sequence in context: A336265 A039428 A043251 * A256515 A238227 A216855

Adjacent sequences: A044028 A044029 A044030 * A044032 A044033 A044034

Keyword

nonn,base

Author

Clark Kimberling

Status

approved