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 A120581 Hankel transform of sum{k=0..n, C(2k,k)*2^k}. 0
 1, 4, -64, -28672, -17825792, -24696061952, -4398046511104, 6413125869375586304, 1279761316857673852911616, 565738597953418785628899770368, 372547299599873882347063111621541888, -5264848781000759906705331926184317767647232 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS FORMULA a(n)=4^(n+C(n,2))(-1)^n*sum{k=0..n, C(n+k,2k)(-2)^(n-k)}; a(n)=8^n*4^C(n,2)*sum{k=0..n, C(n+k,2k)(-2)^(-k)}; a(n)=4^n*4^C(n,2)(-1)^n*A087168(n); CROSSREFS Cf. A120580. Sequence in context: A211214 A229867 A051191 * A146520 A030176 A033635 Adjacent sequences:  A120578 A120579 A120580 * A120582 A120583 A120584 KEYWORD easy,sign AUTHOR Paul Barry, Jun 15 2006 STATUS approved

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Last modified December 7 17:41 EST 2019. Contains 329847 sequences. (Running on oeis4.)