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A230875
a(1)=0; thereafter a(n) = 2^a(ceiling(n/2)).
2
0, 1, 2, 2, 4, 4, 4, 4, 16, 16, 16, 16, 16, 16, 16, 16, 65536, 65536, 65536, 65536, 65536, 65536, 65536, 65536, 65536, 65536, 65536, 65536, 65536, 65536, 65536, 65536
OFFSET
1,3
COMMENTS
a(33) through a(64) are 2^65536.
FORMULA
For n>2, a(n) = a tower of 2's of height ceiling(log_2(n))-1. E.g. a(17) = 2^2^2^2.
CROSSREFS
Sequence in context: A292597 A101656 A090557 * A035660 A302405 A115367
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Nov 07 2013
STATUS
approved