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A222011
Dimensions of finite-dimensional real division algebras.
1
OFFSET
0,2
COMMENTS
In 1958 Michel Kervaire and John Milnor independently proved that any finite-dimensional real division algebra must be of dimension 1, 2, 4, or 8.
FORMULA
a(n) = 2^n = A222010(n) + 1 for n = 0, 1, 2, 3.
EXAMPLE
The real, complex, quaternion, and Cayley numbers are real division algebras of dimensions 1, 2, 4, 8, respectively, so those are members.
CROSSREFS
Cf. A222010.
Sequence in context: A103009 A174393 A153662 * A063864 A186036 A186040
KEYWORD
nonn,fini,full
AUTHOR
Jonathan Sondow, Feb 06 2013
STATUS
approved