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%I #11 Apr 25 2024 13:22:57
%S 1,1,4,14,51,189,709,2683,10220,39130,150438,580328,2245004,8705686,
%T 33828704,131688362,513445147,2004688605,7836832057,30670416703,
%U 120153739079,471143251989,1848978071615,7261781367389,28540427527441,112243216215879,441693646453729
%N a(n) = Sum_{k=0..floor(n/2)} binomial(2*n-k-1,n-2*k).
%F a(n) = [x^n] 1/((1-x-x^2) * (1-x)^(n-1)).
%F a(n) ~ 4^n / sqrt(Pi*n). - _Vaclav Kotesovec_, Apr 16 2024
%F a(n) = A354267(2*n, n). - _Peter Luschny_, Apr 25 2024
%o (PARI) a(n) = sum(k=0, n\2, binomial(2*n-k-1, n-2*k));
%Y Cf. A072547, A114121, A354267.
%K nonn
%O 0,3
%A _Seiichi Manyama_, Apr 10 2024
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