A359045 a(n) = Sum_{1<=iA020985(m).

0, 0, 0, -1, -2, -2, -4, -5, -4, 0, 8, -5, -12, -14, -16, -17, -20, -20, -16, -25, -22, -14, -28, -21, -34, -40, -40, -45, -46, -42, -52, -49, -40, -24, 0, -33, -10, 22, -20, 11, 52, 104, 168, 91, 28, -22, 16, -33, -70, -96, -112, -105, -120, -126, -128, -133

Offset: 0

Author

Chai Wah Wu, Feb 12 2023

Keywords

• sign

Crossrefs

Cf. A020985, A190173, A213626, A213786, A213787.

Programs

Python

def A359045(n): return sum((-1 if (i&(i>>1)).bit_count()&1 else 1)*sum((-1 if (j&(j>>1)).bit_count()&1 else 1)*sum(-1 if (k&(k>>1)).bit_count()&1 else 1 for k in range(j+1,n+1)) for j in range(i+1,n+1)) for i in range(1,n+1))

Formula

a(n) = A213626(n)-A213786(n).