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%I #18 Dec 21 2020 18:11:42
%S 1,2,1,2,1,3,2,3,2,4,2,4,2,4,3,5,3,5,3,5,3,5,3,6,4,6,4,6,4,6,4,7,4,7,
%T 4,7,4,7,5,7,5,8,5,8,5,8,5,8,5,8,5,9,5,9,5,9,6,9,6,9,6,9,6,10,6,10,6,
%U 10,6,10,6,10,6,10,6,10,7,11,7,11,7,11,7,11,7,11,7,11,7,11
%N Define b(1)=1 and for n>1, b(n)=n/b(n-1); then a(n) = floor(b(n)).
%e The first few fractions b(n) are 1, 2, 3/2, 8/3, 15/8, 16/5, 35/16, 128/35, 315/128, 256/63, 693/256, 1024/231, 3003/1024, 2048/429, ...
%t a[n_] := Floor[n!!/(n - 1)!!]; Array[a, 90] (* _Robert G. Wilson v_, Dec 06 2020 *)
%Y Cf. A338719, A338720.
%Y For the numerators and denominators of b(n) see A004731 and A004730.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Nov 29 2020, following a suggestion from _Anchar Koops_, Nov 24 2020
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