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A094120 a(n)=sum(k=1,n,sum(i=1,k,(-2)^valuation(i,2))). 0
0, 1, 0, 0, 4, 9, 12, 16, 12, 9, 4, 0, 0, 1, 0, 0, 16, 33, 48, 64, 84, 105, 124, 144, 156, 169, 180, 192, 208, 225, 240, 256, 240, 225, 208, 192, 180, 169, 156, 144, 124, 105, 84, 64, 48, 33, 16, 0, 0, 1, 0, 0, 4, 9, 12, 16, 12, 9, 4, 0, 0, 1, 0, 0, 64, 129, 192, 256, 324, 393 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..70.

PROG

(PARI) a(n)=sum(k=1, n, sum(i=1, k, (-2)^valuation(i, 2)))

CROSSREFS

Cf. A006519.

Sequence in context: A312853 A312854 A010386 * A066423 A072498 A162643

Adjacent sequences:  A094117 A094118 A094119 * A094121 A094122 A094123

KEYWORD

nonn

AUTHOR

Benoit Cloitre, May 03 2004

STATUS

approved

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Last modified January 23 12:31 EST 2021. Contains 340385 sequences. (Running on oeis4.)