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 A135951 Central terms of triangle A135950, the matrix inverse of triangle A022166. 2
 1, -3, 70, -11160, 12850368, -111842970624, 7558738517524480, -4024873276683363287040, 17013427111087951089139449856, -573105858480900876266937950612226048, 154142404695090288939416498797330749299097600 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS A022166 is the triangle of Gaussian binomial coefficients [n,k] for q = 2. LINKS Table of n, a(n) for n=0..10. MATHEMATICA max = 20; M = Table[QBinomial[n, k, 2], {n, 0, max}, {k, 0, max}] // Inverse; Table[M[[n, (n+1)/2]], {n, 1, max+1, 2}] (* Jean-François Alcover, Apr 09 2016 *) Table[(-1)^n 2^((n-1)n/2) QBinomial[2n, n, 2], {n, 0, 20}] (* Vladimir Reshetnikov, Sep 16 2016 *) PROG (PARI) a(n)=local(q=2, A=matrix(2*n+1, 2*n+1, n, k, if(n>=k, if(n==1 || k==1, 1, prod(j=n-k+1, n-1, 1-q^j)/prod(j=1, k-1, 1-q^j))))^-1); A[2*n+1, n+1] CROSSREFS Cf. A135950, A022166. Sequence in context: A277413 A210920 A140048 * A361254 A093245 A108231 Adjacent sequences: A135948 A135949 A135950 * A135952 A135953 A135954 KEYWORD sign AUTHOR Paul D. Hanna, Dec 08 2007 STATUS approved

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Last modified December 4 14:24 EST 2023. Contains 367563 sequences. (Running on oeis4.)