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A349932
Product of n and its binary ones' complement.
0
0, 2, 0, 12, 10, 6, 0, 56, 54, 50, 44, 36, 26, 14, 0, 240, 238, 234, 228, 220, 210, 198, 184, 168, 150, 130, 108, 84, 58, 30, 0, 992, 990, 986, 980, 972, 962, 950, 936, 920, 902, 882, 860, 836, 810, 782, 752, 720, 686, 650, 612, 572, 530, 486, 440, 392, 342, 290
OFFSET
1,2
FORMULA
a(n) = n*A035327(n).
EXAMPLE
For n = 9, a(9) = 0b1001 * 0b0110 = 9 * 6 = 54.
PROG
(PARI) a(n) = n*bitneg(n, exponent(n)) \\ Andrew Howroyd, Dec 05 2021
(Python)
def a(n): return 0 if n == 0 else n * (n^((1 << n.bit_length()) - 1))
print([a(n) for n in range(1, 58)]) # Michael S. Branicky, Dec 05 2021
CROSSREFS
Cf. A035327.
Sequence in context: A321982 A104014 A007207 * A002929 A112261 A134831
KEYWORD
nonn,base,easy
AUTHOR
Judson Neer, Dec 05 2021
STATUS
approved