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a(n) = hypergeom([1/2 - n/2, -n/2], [-n], -56).
1

%I #8 Feb 18 2024 03:32:03

%S 1,1,15,29,239,645,3991,13021,68895,251189,1215719,4732365,21752431,

%T 88005541,392539575,1624617149,7120171199,29864811285,129547208071,

%U 547654566061,2361315479055,10028479403909,43086896110679,183485607765405,786702153314911,3355500662030581

%N a(n) = hypergeom([1/2 - n/2, -n/2], [-n], -56).

%F a(n) ~ (1 + sqrt(57))^(n+1) / (sqrt(57) * 2^(n+1)). - _Vaclav Kotesovec_, Feb 18 2024

%t Table[HypergeometricPFQ[{1/2 - n/2, -n/2}, {-n}, -56], {n, 0, 30}] (* _Vaclav Kotesovec_, Feb 18 2024 *)

%Y a(n) = A350470(7, n).

%K nonn

%O 0,3

%A _Peter Luschny_, Mar 19 2022