login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

a(n) = hypergeom([1/2 - n/2, -n/2], [-n], -72).
1

%I #8 Feb 18 2024 03:33:51

%S 1,1,19,37,379,1045,7867,26677,168283,648469,3677563,15350005,

%T 81546139,357846229,1825676731,8266908853,41129090011,189933449365,

%U 930257069563,4349059158133,21093686410267,99376751256661,479063106641467,2267844629261365,10890980548807771

%N a(n) = hypergeom([1/2 - n/2, -n/2], [-n], -72).

%F a(n) ~ (1 + sqrt(73))^(n+1) / (sqrt(73) * 2^(n+1)). - _Vaclav Kotesovec_, Feb 18 2024

%t Table[HypergeometricPFQ[{1/2 - n/2, -n/2}, {-n}, -72], {n, 0, 30}] (* _Vaclav Kotesovec_, Feb 18 2024 *)

%Y a(n) = A350470(9, n).

%K nonn

%O 0,3

%A _Peter Luschny_, Mar 19 2022