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A131969 First differences of A020806. 1
3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6, 3, -2, 6, -3, 2, -6 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..77.

FORMULA

a(n)=(1/6)*{-9*(n mod 6)+8*[(n+1) mod 6]-5*[(n+2) mod 6]+9*[(n+3) mod 6]-8*[(n+4) mod 6]+5*[(n+5) mod 6]}, with n>=0 - Paolo P. Lava, Oct 10 2007

a(n)=11*(-1)^n/3-2*A010892(n)/3+7*A010892(n-1)/3, n>0. a(n+6)=a(n). G.f.: (3-2x+6x^2)/((1+x)(1-x+x^2)). [From R. J. Mathar, Oct 24 2008]

CROSSREFS

Sequence in context: A198930 A263353 A248945 * A058971 A186204 A137324

Adjacent sequences:  A131966 A131967 A131968 * A131970 A131971 A131972

KEYWORD

sign

AUTHOR

Paul Curtz, Oct 06 2007

STATUS

approved

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Last modified June 19 04:58 EDT 2021. Contains 345125 sequences. (Running on oeis4.)