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A134314 First differences of A134429. 2
-8, 8, -8, 16, -24, 24, -24, 32, -40, 40, -40, 48, -56, 56, -56, 64, -72, 72, -72, 80, -88, 88, -88, 96, -104, 104, -104, 112, -120, 120, -120, 128, -136, 136, -136, 144, -152, 152, -152, 160, -168, 168, -168, 176, -184, 184, -184, 192, -200, 200, -200, 208 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

Also fourth differences of (A057979 with (4n+3)-th terms negative = 1, n, -1, n+1). Also 8*(without 0, A004525 signed).

First differences: -1, -1, 2, 0, 1, -3, 4, -2, 3, -5, 6, -4, 5, -7, 8, -6, 7, -9 ...; second: 0, 3, -2, 1, -4, 7, -6, 5, -8, 11, -10, 9, -12 ... (cf. A092486); third: 3, -5, 3, -5, 11, -13, 11, -13, 19, -21, 19, -21, 27, -29, 27, -29, ... for which d(2n)+d(2n+1)=-A007395.

FORMULA

a(n)= -2*a(n-1)-2*a(n-2)-2*a(n-3)-a(n-4) = -8*(-1)^n*A004525(n+1). G.f.: -8(1+x+x^2)/((1+x^2)(1+x)^2). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 07 2009]

MAPLE

A134429 := proc(n) npr := floor(n/4) ; if (n mod 4 =0) or (n mod 4 = 2) then 8*npr+3 ; else -8*npr-5 ; fi; end: A134314 := proc(n) A134429(n+1)-A134429(n) ; end: seq(A134314(n), n=0..80) ; [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 07 2009]

CROSSREFS

Sequence in context: A186985 A203127 A023415 * A136050 A077106 A195717

Adjacent sequences:  A134311 A134312 A134313 * A134315 A134316 A134317

KEYWORD

sign,easy

AUTHOR

Paul Curtz (bpcrtz(AT)free.fr), Jan 30 2008

EXTENSIONS

Edited by N. J. A. Sloane (njas(AT)research.att.com), Mar 23 2008

More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 07 2009

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Last modified February 14 18:47 EST 2012. Contains 205663 sequences.