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A097141 Expansion of x(1+2x)/(1+x)^2. 1
0, 1, 0, -1, 2, -3, 4, -5, 6, -7, 8, -9, 10, -11, 12, -13, 14, -15, 16, -17, 18, -19, 20, -21, 22, -23, 24, -25, 26, -27, 28, -29, 30, -31, 32, -33, 34, -35, 36, -37, 38, -39, 40, -41, 42, -43, 44, -45, 46, -47, 48, -49, 50, -51, 52, -53, 54, -55, 56, -57, 58, -59, 60 (list; graph; refs; listen; history; internal format)
OFFSET

0,5

COMMENTS

Partial sums of A097140. Binomial transform is x(1+x)/(1-x), or {0,1,2,2,2,2,....}. Second binomial transform is x/((1-x)^2(1 - 2x)), or Eulerian numbers A000295(n+1).

FORMULA

a(n)=(n-2)(-1)^n+2*0^n; a(n)=-2a(n-1)-a(n-2), n>2.

a(n)=A099570(n), n>1. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Dec 15 2008]

CROSSREFS

Cf. A040000.

Sequence in context: A167976 A024000 * A199969 A160356 A001478 A001489

Adjacent sequences:  A097138 A097139 A097140 * A097142 A097143 A097144

KEYWORD

easy,sign

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Jul 29 2004

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Last modified February 14 16:24 EST 2012. Contains 205635 sequences.