A224074 - OEIS

A224074

Number of root classes of words in F_2 whose minimal words have length n.

1, 0, 0, 0, 2, 0, 0, 0, 13, 0, 0, 0, 304, 0, 0, 0, 11395, 0, 0, 0, 478444, 0, 0, 0

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OFFSET

0,5

COMMENTS

F_2 is the free group on two generators.

a(n) = 0 if n is not divisible by 4.

LINKS

Bobbe Cooper and Eric Rowland, Growing words in the free group on two generators, Illinois Journal of Mathematics 55 (2011) 417-426.

Bobbe Cooper and Eric Rowland, Classification of automorphic conjugacy classes in the free group on two generators, Algorithmic Problems of Group Theory, Their Complexity, and Applications to Cryptography, edited by Delaram Kahrobaei and Vladimir Shpilrain, Contemporary Mathematics 633 (2015) 13-40.

CROSSREFS

A224073 is the number of all equivalence classes.

KEYWORD

nonn,hard,more

AUTHOR

Eric Rowland, Mar 30 2013

STATUS

approved