A044374 Numbers n such that string 4,2 occurs in the base 10 representation of n but not of n-1.

42, 142, 242, 342, 420, 442, 542, 642, 742, 842, 942, 1042, 1142, 1242, 1342, 1420, 1442, 1542, 1642, 1742, 1842, 1942, 2042, 2142, 2242, 2342, 2420, 2442, 2542, 2642, 2742, 2842, 2942, 3042, 3142, 3242, 3342, 3420, 3442

Offset

1,1

Links

Table of n, a(n) for n=1..39.

Mathematica

SequencePosition[Table[If[SequenceCount[IntegerDigits[n], {4, 2}]>0, 1, 0], {n, 3500}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Mar 30 2018 *)

Crossrefs

Sequence in context: A002759 A346856 A330939 * A044755 A262424 A230932

Adjacent sequences: A044371 A044372 A044373 * A044375 A044376 A044377

Keyword

nonn,base

Author

Clark Kimberling

Status

approved