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%I #11 Aug 19 2020 11:27:23
%S 1,3,9,39,197,1187,8309,66476,598287,5982879,65811677,789740126,
%T 10266621646,143732703044,2155990545670,34495848730735,
%U 586429428422497,10555729711604956,200558864520494172,4011177290409883459
%N a(n) = floor(exp(1/2)*n!).
%H Robert Israel, <a href="/A030799/b030799.txt">Table of n, a(n) for n = 1..449</a>
%F a(n+1) = (n+1)*a(n) + A068453(n+1). - _Robert Israel_, Oct 16 2019
%p f:= n -> floor(exp(1/2)*n!):
%p map(f, [$1..30]); # _Robert Israel_, Oct 16 2019
%t Floor[Exp[1/2]Range[20]!] (* _Harvey P. Dale_, Aug 19 2020 *)
%Y Cf. A068453.
%K nonn
%O 1,2
%A _Simon Plouffe_