login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A305594 Number of cyclic binary sequences of length n containing no abelian 4th powers. 0
2, 3, 4, 4, 4, 8, 10, 14, 12, 20, 34, 33, 52, 61, 76, 96, 126, 200, 258, 442, 568 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Two length-n sequences are considered to be the same in the cyclic sense if one is a cyclic shift of the other.

An abelian 4th power is a word of the form x x' x'' x''', where x', x'', x''' are all permutations of x.

LINKS

Table of n, a(n) for n=1..21.

EXAMPLE

a(7) = 10, and the cyclic words are {0001001, 0001011, 0001101, 0010011, 0010101, 0010111, 0011011, 0011101, 0101011, 0110111}.

CROSSREFS

Sequence in context: A076410 A309941 A211509 * A320778 A058277 A065852

Adjacent sequences:  A305591 A305592 A305593 * A305595 A305596 A305597

KEYWORD

nonn,more

AUTHOR

Jeffrey Shallit, Jun 05 2018

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 22 14:33 EST 2020. Contains 332136 sequences. (Running on oeis4.)