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A327494 a(n) = numerator(r(n)) where r(n) = Sum_{j=0..n} j!/(2^j*floor(j/2)!)^2.

%I A327494 #14 Oct 03 2019 06:51:50
%S A327494 1,5,11,47,191,779,1563,6287,50331,201639,403341,1614057,6456459,
%T A327494 25828839,51658107,206638863,3306228243,13225022367,26450056889,
%U A327494 105800458501,423201880193,1692808490741,3385617069661,13542470306761,108339763130127,433359069421483
%N A327494 a(n) = numerator(r(n)) where r(n) = Sum_{j=0..n} j!/(2^j*floor(j/2)!)^2.
%F A327494 Lim_{n -> oo} r(n) = (4/3)^(3/2) = A118273.
%e A327494 r(n) = 1, 5/4, 11/8, 47/32, 191/128, 779/512, 1563/1024, 6287/4096, 50331/32768, 201639/131072, ...
%p A327494 A327494 := n -> numer(add(j!/(2^j*iquo(j,2)!)^2, j=0..n)):
%p A327494 seq(A327494(n), n=0..25);
%o A327494 (PARI) a(n)={ numerator(sum(j=0, n, j!/(2^j*(j\2)!)^2)) } \\ _Andrew Howroyd_, Sep 28 2019
%o A327494 (Julia)
%o A327494 A327494(n) = sum(<<(A163590(k), A327492(n) - A327492(k)) for k in 0:n) # _Peter Luschny_, Oct 03 2019
%Y A327494 Denominators are in A327493.
%Y A327494 Cf. A327491, A327492, A327493, A327495, A118273, A163590.
%K A327494 nonn,frac
%O A327494 0,2
%A A327494 _Peter Luschny_, Sep 27 2019