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A156249 a(n)=sum(k=1,n,(-1)^k*A000002(2*k-1)) 0
-1, 1, 0, 1, -1, 1, 0, 2, 1, 3, 1, 2, 1, 3, 2, 3, 1, 3, 2, 4, 3, 4, 2, 4, 3, 4, 2, 3, 1, 2, 1, 3, 1, 2, 0, 1, 0, 2, 0, 1, -1, 1, 0, 2, 0, 1, -1, 0, -1, 1, 0, 1, -1, 1, 0, 2, 1, 2, 0, 2, 1, 3, 2, 4, 2, 3, 2, 4, 3, 5, 4, 5, 3, 5, 4, 6, 4, 5, 4, 6, 5, 7, 5, 6, 4, 6, 5, 6, 4, 5, 3, 5, 4, 5, 3, 4, 3, 5, 3, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,8

LINKS

Table of n, a(n) for n=1..100.

CROSSREFS

Sequence in context: A111376 A241664 A157226 * A187808 A164677 A001511

Adjacent sequences:  A156246 A156247 A156248 * A156250 A156251 A156252

KEYWORD

sign

AUTHOR

Benoit Cloitre, Feb 07 2009

STATUS

approved

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Last modified September 18 05:49 EDT 2014. Contains 246893 sequences.