A164343 A positive integer is included if it is a square that contains the same number of 0's as 1's when represented in binary.

9, 49, 169, 225, 625, 841, 961, 2916, 3249, 3721, 3969, 10609, 12100, 12769, 13924, 14641, 15625, 16129, 39601, 41209, 42849, 44944, 45369, 45796, 47524, 52900, 56644, 58081, 60516, 62001, 64009, 65025, 151321, 154449, 155236, 156025, 161604, 163216, 167281

Offset: 1

Author

Leroy Quet, Aug 13 2009

Keywords

• base
• nonn

Links

• Michael S. Branicky, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Harvey P. Dale)

Crossrefs

Cf. A031443, A164344.

Programs

Mathematica

Select[Range[500]^2,DigitCount[#,2,1]==DigitCount[#,2,0]&] (* Harvey P. Dale, Nov 18 2014 *)

Python

def bal(n): return n and n.bit_length() == n.bit_count() * 2
print([s for s in (k*k for k in range(403)) if bal(s)]) # Michael S. Branicky, Jul 12 2022

Extensions

More terms from Sean A. Irvine, Oct 08 2009