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!)
A051881 Number of subgroups of order n in special orthogonal group SO(3). 2
1, 1, 1, 2, 1, 2, 1, 2, 1, 2, 1, 3, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 3, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 3, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..12000

FORMULA

Has period 1, 2 except for a(2) = 1, a(12) = a(24) = a(60) = 3.

EXAMPLE

The groups are "nn", of order n; "22n", of order 2n; "332", "432", "532" of orders 12,24,60.

MATHEMATICA

a[2] = 1; a[12|24|60] = 3; a[n_] := 2-Mod[n, 2]; Array[a, 105] (* Jean-Fran├žois Alcover, Nov 12 2015 *)

PROG

(PARI) a(n)=if(n==2||n==12||n==24||n==60, if(n>2, 3, 1), if(n%2, 1, 2)) \\ Charles R Greathouse IV, Nov 10 2015

CROSSREFS

The main sequences concerned with group theory are A000001, A000679, A001034, A001051, A001228, A005180, A000019, A000637, A000638, A002106, A005432, A051881.

Sequence in context: A160979 A323287 A167679 * A338731 A081757 A323880

Adjacent sequences:  A051878 A051879 A051880 * A051882 A051883 A051884

KEYWORD

nonn,easy,nice

AUTHOR

J. H. Conway

EXTENSIONS

More terms from James A. Sellers and David W. Wilson Dec 16 1999

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 September 22 13:48 EDT 2021. Contains 347607 sequences. (Running on oeis4.)