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%I #20 Dec 29 2018 11:13:32
%S 1,-2,-3,-11,-49,-244,-1301,-7265,-41945,-248357,-1499838,-9202478,
%T -57204263,-359491066,-2280171089,-14578108497,-93850280001,
%U -607856133804,-3958143058643,-25897182540675,-170164359751174,-1122422557526850,-7429480035700452
%N Reciprocal of g.f. for A007863.
%H Seiichi Manyama, <a href="/A011365/b011365.txt">Table of n, a(n) for n = 0..500</a>
%F a(n) = -Sum_{i=0..n} binomial(n+i-2,n-2)*binomial(n+i-1,n-i))/(n-1), n>1; a(0)=1, a(1) = -2. - _Vladimir Kruchinin_, Feb 15 2013
%o (PARI) a(n) = if (n==0, 1, if (n==1, -2, -sum(i=0, n, binomial(n+i-2,n-2)*binomial(n+i-1,n-i))/(n-1))); \\ _Michel Marcus_, Dec 29 2018
%Y Cf. A007863.
%K sign
%O 0,2
%A _N. J. A. Sloane_
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