A079074 Sum of numbers < n having in binary representation the same number of 0's and 1's as n.

0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 9, 0, 19, 11, 24, 0, 0, 0, 17, 0, 35, 19, 40, 0, 55, 62, 87, 23, 113, 50, 79, 0, 0, 0, 33, 0, 67, 35, 72, 0, 103, 110, 151, 39, 193, 82, 127, 0, 143, 237, 286, 173, 336, 224, 277, 47, 388, 331, 388, 102, 446, 161, 222, 0, 0, 0, 65, 0, 131, 67, 136, 0

Offset: 0

Author

Reinhard Zumkeller, Dec 21 2002

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 0..16383

Crossrefs

Cf. A079072, A079073, A079071, A007088, A023416, A000120.

Programs

Maple

f:= n-> (x-> (t-> t*(t+1)/2+x[2])(x[1]+x[2]))(add(
    `if`(i=0, [1, 0], [0, 1]), i=convert(n, base, 2))):
b:= proc(n) b(n):= b(n-1)+n*x^f(n) end: b(-1):=0:
a:= n-> coeff(b(n-1), x, f(n)):
seq(a(n), n=0..150);  # Alois P. Heinz, Feb 08 2018

Mathematica

bdQ[m_,n_]:=Module[{a=DigitCount[m,2,0],b=DigitCount[m,2,1], c= DigitCount[ n,2,0], d=DigitCount[ n,2,1]}, a==c&&b==d]; Table[Total[ Select[Range[n-1],bdQ[#,n]&]],{n,80}] (* Harvey P. Dale, Sep 08 2011 *)