A230851 Numbers with divisors which are half odious (A000069) and half evil (A001969).

3, 5, 6, 10, 12, 17, 20, 23, 24, 29, 33, 34, 39, 40, 43, 46, 48, 53, 57, 58, 63, 65, 66, 68, 69, 71, 78, 80, 83, 86, 87, 89, 92, 95, 96, 101, 105, 106, 111, 113, 114, 115, 116, 117, 119, 123, 125, 126, 130, 132, 136, 138, 139, 141, 142, 145, 149, 156, 160, 163, 166, 171, 172, 174, 177, 178, 183

Offset: 1

Author

Juri-Stepan Gerasimov, Oct 31 2013

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000069, A001969, A167171, A227872.

Programs

Mathematica

aQ[n_] := DivisorSum[n, (-1)^DigitCount[#, 2][[1]] &] == 0; Select[Range[200], aQ] (* Amiram Eldar, Sep 23 2019 *)

PARI

is(n)=!sumdiv(n,d,(-1)^hammingweight(d)) \\ Charles R Greathouse IV, Oct 31 2013

Formula

Numbers n such that d(n) = 2*A227872(n) where A227872(n) is number of odious divisors of n.

Extensions

Corrected by Charles R Greathouse IV, Oct 31 2013