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 A102224 Column 0 of the matrix square of A102220, which equals the lower triangular matrix: [2*I - A008459]^(-1). 0
 1, 2, 14, 200, 4814, 174752, 8909168, 606818060, 53211837134, 5838211285616, 783434682568664, 126221710572107900, 24043148814317769584, 5344827109234104188348, 1371307353540074156012828 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS A102221 is column 0 of A102220. Triangle A008459 consists of the squared binomial coefficients. LINKS FORMULA a(n) = Sum_{k=0..n} C(n, k)^2*A102221(k)*A102221(n-k). Sum_{n>=0} a(n)*x^n/n!^2 = 1/(2-BesselI(0,2*sqrt(x)))^2. - Vladeta Jovovic, Jul 17 2006 EXAMPLE Given A102221 = [1,1,5,55,1077,32951,1451723,87054773,...], then this sequence results from a type of self-convolution of A102221: a(2) = 14 = 1^2*1*5 + 2^2*1*1 + 1^2*5*1, a(3) = 200 = 1^2*1*55 + 3^2*1*5 + 3^2*5*1 + 1^2*55*1. PROG (PARI) {a(n)=(matrix(n+1, n+1, i, j, if(i==j, 2, 0)-binomial(i-1, j-1)^2)^-2)[n+1, 1]} CROSSREFS Cf. A102220, A102221, A008459. Sequence in context: A090300 A213977 A322196 * A123543 A279452 A262008 Adjacent sequences:  A102221 A102222 A102223 * A102225 A102226 A102227 KEYWORD nonn AUTHOR Paul D. Hanna, Dec 31 2004 STATUS approved

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Last modified September 19 21:42 EDT 2020. Contains 337184 sequences. (Running on oeis4.)