A059012 Numbers that have an even number of 0's and 1's in their binary expansion.

3, 9, 10, 12, 15, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58, 60, 63, 129, 130, 132, 135, 136, 139, 141, 142, 144, 147, 149, 150, 153, 154, 156, 159, 160, 163, 165, 166, 169, 170, 172, 175, 177, 178, 180, 183, 184, 187, 189, 190, 192, 195, 197, 198

Offset: 1

Author

Patrick De Geest, Dec 15 2000

Keywords

• nonn
• base
• easy

Comments

Intersection of A001969 and A059010.

Examples

			36 is in the sequence because 36 = 100100_10. '100100' has two 1's and four 0's. - _Indranil Ghosh_, Feb 10 2017
		

Links

• Indranil Ghosh, Table of n, a(n) for n = 1..32768

Crossrefs

Cf. A000069, A001969, A059009-A059014.

Programs

Mathematica

Select[Range[200],AllTrue[{DigitCount[#,2,0],DigitCount[#,2,1]},EvenQ]&] (* Harvey P. Dale, Aug 16 2021 *)

PARI

is(n)=hammingweight(n)%2==0 && hammingweight(bitneg(n, #binary(n)))%2==0 \\ Charles R Greathouse IV, Mar 26 2013

Python

i=0
j=1
while j<=300:
    if bin(i)[2:].count("1")%2 == 0 == bin(i)[2:].count("0")%2:
        print(str(j)+" "+str(i))
        j+=1
    i+=1 # Indranil Ghosh, Feb 10 2017