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A156550 5*(-1)^n*A078008(n). 0
5, 0, 10, -10, 30, -50, 110, -210, 430, -850, 1710, -3410, 6830, -13650, 27310, -54610, 109230, -218450, 436910, -873810, 1747630, -3495250, 6990510, -13981010, 27962030, -55924050, 111848110, -223696210, 447392430, -894784850, 1789569710, -3579139410 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

FORMULA

a(n) = A140966(n)+A140966(n+2).

a(n) = 3*A140966(n)-A140966(n+1). a(n+1)=10*(-1)^n*A001045(n).

G.f.: 5*(1+x)/(1+x-2*x^2). - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 23 2009

CROSSREFS

Sequence in context: A176325 A010481 A022898 * A088307 A007392 A052401

Adjacent sequences:  A156547 A156548 A156549 * A156551 A156552 A156553

KEYWORD

sign,easy,less

AUTHOR

Paul Curtz (bpcrtz(AT)free.fr), Feb 09 2009

EXTENSIONS

Edited and extended by R. J. Mathar (mathar(AT)strw.leidenuniv.nl) Feb 23 2009

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Last modified February 16 01:31 EST 2012. Contains 205860 sequences.