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A322851
a(n) = floor(2^(2^(n/2))-1).
1
1, 1, 3, 6, 15, 49, 255, 2544, 65535, 6479346, 4294967295, 41981937869755, 18446744073709551615, 1762483107300123635910219390, 340282366920938463463374607431768211455
OFFSET
0,3
COMMENTS
A051179 is a bisection of this sequence.
MATHEMATICA
Array[Floor[2^(2^(#/2)) - 1] &, 15, 0] (* Michael De Vlieger, Jan 04 2019 *)
PROG
(PARI) a(n) = floor(2^(2^(n/2)))-1; \\ Michel Marcus, Jan 15 2019
CROSSREFS
Cf. A051179. A322852 is the base-e analog.
Sequence in context: A277063 A051169 A051610 * A230950 A370888 A327437
KEYWORD
nonn,easy
AUTHOR
Greg Huber, Dec 28 2018
STATUS
approved