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Product of n and its binary ones' complement.
0

%I #18 Dec 19 2021 04:23:12

%S 0,2,0,12,10,6,0,56,54,50,44,36,26,14,0,240,238,234,228,220,210,198,

%T 184,168,150,130,108,84,58,30,0,992,990,986,980,972,962,950,936,920,

%U 902,882,860,836,810,782,752,720,686,650,612,572,530,486,440,392,342,290

%N Product of n and its binary ones' complement.

%F a(n) = n*A035327(n).

%e For n = 9, a(9) = 0b1001 * 0b0110 = 9 * 6 = 54.

%o (PARI) a(n) = n*bitneg(n, exponent(n)) \\ _Andrew Howroyd_, Dec 05 2021

%o (Python)

%o def a(n): return 0 if n == 0 else n * (n^((1 << n.bit_length()) - 1))

%o print([a(n) for n in range(1, 58)]) # _Michael S. Branicky_, Dec 05 2021

%Y Cf. A035327.

%K nonn,base,easy

%O 1,2

%A _Judson Neer_, Dec 05 2021