A045107 Numbers whose base-4 representation contains exactly four 1's and two 2's.

1370, 1382, 1385, 1430, 1433, 1445, 1622, 1625, 1637, 1685, 2390, 2393, 2405, 2453, 2645, 4442, 4454, 4457, 4502, 4505, 4517, 4694, 4697, 4709, 4757, 5210, 5222, 5225, 5270, 5273, 5285, 5402, 5414, 5417, 5450, 5474

Offset

1,1

Links

Table of n, a(n) for n=1..36.

Mathematica

Select[Range[6000], DigitCount[#, 4, 1]==4&&DigitCount[#, 4, 2]==2&] (* Harvey P. Dale, Nov 21 2012 *)

Crossrefs

Cf. A007090.

Sequence in context: A167724 A156574 A145697 * A031752 A031662 A251567

Adjacent sequences: A045104 A045105 A045106 * A045108 A045109 A045110

Keyword

nonn,base

Author

Clark Kimberling

Status

approved