0,5

Partial sums at positions 2^m-1 = m*2^(m-2) for m>=2.

Partial sums at 2^m-1 are:

at 2^2-1 (m=2): 0+1+1+0 = 2 = 2*2^(2-2),

at 2^3-1 (m=3): 0+1+1+0+2+1+1+0 = 6 = 3*2^(3-2),

at 2^4-1 (m=4): 0+1+1+0+2+1+1+0+2+1+3+0+2+1+1+0 = 16 = 4*2^(4-2).

(PARI) {a(n)=sum(k=0, (n-1)\2, if(bitxor(n-k, k)==2^valuation(bitxor(n-k, k), 2), 1, 0))}

Cf. A047999, A101309.

Sequence in context: A143792 A029375 A071462 this_sequence A060582 A060450 A025860

Adjacent sequences: A101976 A101977 A101978 this_sequence A101980 A101981 A101982

nonn

Paul D. Hanna (pauldhanna(AT)juno.com), Dec 23 2004