login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A104000 Square array T(r,m) read by antidiagonals: number of cyclically reduced words of length m in F_r. 0
2, 4, 2, 6, 12, 2, 8, 30, 28, 2, 10, 56, 126, 84, 2, 12, 90, 344, 630, 244, 2, 14, 132, 730, 2408, 3126, 732, 2, 16, 182, 1332, 6570, 16808, 15630, 2188, 2, 18, 240, 2198, 14652, 59050, 117656, 78126, 6564, 2, 20, 306, 3376, 28574, 161052, 531450 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..51.

I. Rivin, Growth in free groups (and other stories)

FORMULA

T(r, m) = (2r-1)^m + 1 + (r-1)(1+(-1)^m).

EXAMPLE

2,2,2,2,2,2,2,2,2,

4,12,28,84,244,732,2188,6564,19684,

6,30,126,630,3126,15630,78126,390630,1953126,

8,56,344,2408,16808,117656,823544,5764808,40353608,

10,90,730,6570,59050,531450,4782970,43046730,387420490,

12,132,1332,14652,161052,1771572,19487172,214358892,2357947692,

14,182,2198,28574,371294,4826822,62748518,815730734,10604499374,

CROSSREFS

Sequence in context: A205721 A085190 A285702 * A199943 A013599 A276528

Adjacent sequences:  A103997 A103998 A103999 * A104001 A104002 A104003

KEYWORD

nonn,tabl

AUTHOR

Ralf Stephan, Feb 26 2005

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 August 21 18:26 EDT 2019. Contains 326168 sequences. (Running on oeis4.)