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%I #20 Sep 27 2016 08:09:54
%S 1,1,9,169,5329,251001,16410601,1416242689,155514288609,
%T 21128299481809,3474052208270281,679096541717605881,
%U 155504946117339546289,41199419449380747871369,12496348897836314700506409
%N a(n) = A000262(n)^2.
%F Recurrence: (2*n+3)*a(n+3)-(2*n+5)*(3*n^2+13*n+13)*a(n+2)+(n+2)*(n+1)*(2*n+3)*(3*n^2+13*n+13)*a(n+1)-n^2*(n+1)^3*(n+2)*(2 n+5)*a(n) = 0.
%F Asymptotic: a(n) ~ exp(-2*n+4*sqrt(n)-1)*n^(2*n-1/2)/2 * (1 - 5/(24*sqrt(n)) - 35/(1152*n)).
%t Table[HypergeometricPFQ[{-n+1,-n},{},1]^2,{n,0,100}]
%o (Maxima) makelist(hypergeometric([-n+1,-n],[],1)^2,n,0,12);
%Y Cf. A000262, A105278, A008297, A276964.
%K nonn
%O 0,3
%A _Emanuele Munarini_, Sep 27 2016
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