A030814 - OEIS

%I #11 Mar 15 2020 02:19:13

%S 1,3,11,46,230,1382,9675,77402,696624,6966242,76628663,919543959,

%T 11954071471,167357000594,2510355008911,40165680142590,

%U 682816562424042,12290698123632756,233523264349022367,4670465286980447352

%N a(n) = floor(exp(15/23) * n!).

%e 15/23 = 0.65217391304347826...

%e e^(15/23) = 1.91970957781434403430534711... so a(1) = 1.

%e e^(15/23) * 2! = 3.83941915562868806861... so a(2) = 3.

%e e^(15/23) * 3! = 11.518257466886064205832... so a(3) = 11.

%t Floor[Exp[15/23] Range[20]!] (* _Harvey P. Dale_, Feb 11 2015 *)

%Y Cf. A021027 (1/23).

%K nonn,easy

%O 1,2

%A _Simon Plouffe_