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 A156125 a(n)=10^n*C(2n,n)/C(n+3,3). 1
 1, 5, 60, 1000, 20000, 450000, 11000000, 286000000, 7800000000, 221000000000, 6460000000000, 193800000000000, 5943200000000000, 185725000000000000, 5899500000000000000, 190095000000000000000, 6203100000000000000000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Hankel transform is 10^(n^2-1+0^n)*A156126(n). LINKS FORMULA G.f.: F(1/2,1;4;40x); a(n)=6*10^n*A000108(n)/((n+2)(n+3))=10^(n-1)*A007272(n). (n+3)*a(n) +20*(1-2*n)*a(n-1)=0. - R. J. Mathar, Oct 25 2012 CROSSREFS Sequence in context: A192948 A234528 A277300 * A260776 A128574 A120976 Adjacent sequences:  A156122 A156123 A156124 * A156126 A156127 A156128 KEYWORD easy,nonn AUTHOR Paul Barry, Feb 04 2009 STATUS approved

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