A135120 Numbers such that the digital sum base 2 and the digital sum base 3 and the digital sum base 10 all are equal.

1, 21, 222, 223, 1230, 1231, 1502, 2200, 2201, 3012, 3013, 10431, 12214, 12215, 12250, 12251, 14102, 15003, 15021, 16011, 20040, 20041, 22130, 23211, 23230, 23231, 24003, 30070, 30071, 30105, 30231, 30321, 31005, 31150, 31151, 31420

Offset

1,2

Links

G. C. Greubel, Table of n, a(n) for n = 1..1100

Example

a(2)=21, since ds_2(21)=ds_3(21)=ds_10(21)=3.

Mathematica

Select[Range[5000], Total[IntegerDigits[#, 2]] == Total[IntegerDigits[#, 3]] ==  Total[IntegerDigits[#, 10]] &] (* G. C. Greubel, Sep 26 2016 *)

Prog

(PARI) is(n)=my(t=sumdigits(n)); t==hammingweight(n) && t==sumdigits(n, 3) \\ Charles R Greathouse IV, Sep 26 2016

Crossrefs

Cf. A000040, A007953, A054899, A131451, A133620, A133900, A134599, A135110.

Sequence in context: A008421 A134585 A165402 * A027812 A171112 A171108

Adjacent sequences: A135117 A135118 A135119 * A135121 A135122 A135123

Keyword

nonn,base

Author

Hieronymus Fischer, Dec 24 2007

Status

approved