A055452 - OEIS

%I #16 Jan 30 2024 06:25:37

%S 1,3,5,19,75,305,1270,5390,23236,101480,448085,1997115,8973255,

%T 40602093,184853055,846206025,3892585325,17984308775,83417287855,

%U 388297304825,1813341109825,8493372326675,39889629750600

%N a(n) = T(n,n-2), array T as in A055450.

%H G. C. Greubel, <a href="/A055452/b055452.txt">Table of n, a(n) for n = 2..500</a>

%F a(n) = 5*hypergeometric([4-n,7/2],[5],-4), for n>3. - _Peter Luschny_, Aug 15 2012

%t Table[If[n<4, 2*n-3, 5*Hypergeometric2F1[4-n,7/2,5,-4]], {n,2,40}] (* _G. C. Greubel_, Jan 29 2024 *)

%o (Magma) [n le 3 select 2*n-3 else Round(5*HypergeometricSeries2F1(4-n,7/2,5,-4)): n in [2..40]]; // _G. C. Greubel_, Jan 29 2024

%o (SageMath)

%o def A055452(n): return 2*n-3 if n<4 else 5*hypergeometric([4-n,7/2],[5],-4).simplify()

%o [A055452(n) for n in range(2,41)] # _G. C. Greubel_, Jan 29 2024

%Y Cf. A055450, A055451, A055453, A055454, A055455.

%K nonn

%O 2,2

%A _Clark Kimberling_, May 18 2000