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 A088675 Eigenfunction of a sequence transformation. 0
 0, 1, -2, 8, -36, 160, -656, 2368, -7664, 29440, -184896, 1174272, -3395200, -21222400, 178961920, 1638189056, -27449296640, -28875071488, 3234263731200, -10138343231488, -422012179953664, 3426627065331712, 59293997091528704 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS G.f. A(x) satisfies x=(1+4*A(x))A(A(x)). LINKS Table of n, a(n) for n=0..22. FORMULA a(n)=T(n,1), T(n,m)=1/2*(sum(k=1..n-m, 4^k*T(n-m,k)*binomial(k+m-1,m-1)*(-1)^(k))-sum(k=m+1..n-1, T(n,k)*T(k,m))), n>m, T(n,n)=1. [Vladimir Kruchinin, May 04 2012] PROG (PARI) a(n)=local(A); if(n<1, 0, A=x; for(k=1, n, A=Pol(A+serreverse(A+x*O(x^k))/(1+4*x))/2); polcoeff(A, n)) (Maxima) T(n, m):=if n=m then 1 else 1/2*(sum(4^k*T(n-m, k)*binomial(k+m-1, m-1)*(-1)^(k), k, 1, n-m)-sum(T(n, k)*T(k, m), k, m+1, n-1)); makelist(T(n, 1), n, 1, 10); [Vladimir Kruchinin, May 04 2012] CROSSREFS Sequence in context: A123290 A321110 A228791 * A228197 A326244 A027743 Adjacent sequences: A088672 A088673 A088674 * A088676 A088677 A088678 KEYWORD sign AUTHOR Michael Somos, Oct 04 2003 STATUS approved

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Last modified September 30 18:09 EDT 2023. Contains 365792 sequences. (Running on oeis4.)