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A098820
Periodicity of entries in the first row of a Laver Table of size 2^n.
0
1, 1, 2, 4, 4, 8, 8, 8, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16
OFFSET
0,3
COMMENTS
All sequence elements are powers of 2. The first n for which a(n)=32 is at least A(9,A(8,A(8,255))), where A denotes the Ackermann function (R. Dougherty). If a rank-into-rank exists, then the sequence is diverging (R. Laver).
LINKS
Richard Laver, On the Algebra of Elementary Embeddings of a Rank into Itself, Advances in Mathematics 110, p. 334, 1995
Wikipedia, Laver table
EXAMPLE
a(4)=4 because the entries in the first row of the Laver table of size 4^2=16 are 2,12,14,16,2,12,14,16,2,12,14,16,2,12,14,16 (and thus repeat with a periodicity of 4).
CROSSREFS
Sequence in context: A265560 A265544 A290221 * A296613 A062383 A034583
KEYWORD
nonn
AUTHOR
Christian Schroeder, Oct 08 2004
EXTENSIONS
More terms from Adam P. Goucher, Dec 18 2013
STATUS
approved