A045115 Numbers whose base-4 representation contains exactly one 1 and one 3.

7, 13, 19, 27, 28, 30, 39, 45, 49, 52, 54, 57, 67, 75, 76, 78, 99, 107, 108, 110, 112, 114, 120, 122, 135, 141, 147, 155, 156, 158, 167, 173, 177, 180, 182, 185, 193, 196, 198, 201, 208, 210, 216, 218, 225, 228, 230, 233, 259, 267

Offset

1,1

Links

Table of n, a(n) for n=1..50.

Mathematica

Select[Range[300], DigitCount[#, 4, 1]==DigitCount[#, 4, 3]==1&] (* Harvey P. Dale, Jul 24 2021 *)

Crossrefs

Cf. A007090.

Sequence in context: A004082 A246294 A039281 * A331830 A221027 A211431

Adjacent sequences: A045112 A045113 A045114 * A045116 A045117 A045118

Keyword

nonn,base

Author

Clark Kimberling

Status

approved