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 A174108 Hankel transform of A174107 and A061639(n+1). 2
 1, 0, -9, -81, -729, 0, 531441, 43046721, 3486784401, 0, -205891132094649, -150094635296999121, -109418989131512359209, 0, 523347633027360537213511521, 3433683820292512484657849089281 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Table of n, a(n) for n=0..15. FORMULA a(n)=((1/2-sqrt(2)/4)*(cos(3*pi*n/4)+sin(3*pi*n/4))+(1/2+sqrt(2)/4)*(cos(3*pi*n/4)-sin(3*pi*n/4)))*9^floor((n+1)^2/8). CROSSREFS Sequence in context: A206694 A125910 A171283 * A254435 A267790 A268014 Adjacent sequences: A174105 A174106 A174107 * A174109 A174110 A174111 KEYWORD easy,sign AUTHOR Paul Barry, Mar 07 2010 STATUS approved

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Last modified June 2 10:25 EDT 2023. Contains 363097 sequences. (Running on oeis4.)