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%I #27 Feb 25 2019 21:00:57
%S 1,1,3,6,15,49,255,2544,65535,6479346,4294967295,41981937869755,
%T 18446744073709551615,1762483107300123635910219390,
%U 340282366920938463463374607431768211455
%N a(n) = floor(2^(2^(n/2))-1).
%C A051179 is a bisection of this sequence.
%t Array[Floor[2^(2^(#/2)) - 1] &, 15, 0] (* _Michael De Vlieger_, Jan 04 2019 *)
%o (PARI) a(n) = floor(2^(2^(n/2)))-1; \\ _Michel Marcus_, Jan 15 2019
%Y Cf. A051179. A322852 is the base-e analog.
%K nonn,easy
%O 0,3
%A _Greg Huber_, Dec 28 2018