{qi}:
All of the square roots of 1 such that i,j,
qi + qj
0.
Thus this is all the square roots of 1 leaving out the additive inverses. For k=2, 1 is the only qi. For k=10, there would be two qi, 1 and ...18751. (Note that you could actually choose any of the square roots of 1 to be your qi's as long as none of them are additive inverses.) For k=30, there are four qi.
Lq:
{ r1*q1 + r2*q*2 + ... +
rn*qn | ri
Lr }
For any number base that's a prime or power of a prime, Lq = Lr . This is because 1 is the only qi.
Addition and multiplication are easy to define for Lq . We will look at L10q as an example.
(a + bq) + (c + dq) = (a + c) + (b + d)q
(a + bq) * (c + dq) = (ac+bd) + (ad+bc)q
Clearly Lq is closed under addition and multiplication. Thus Lq is a commutative ring. Lr is a subring of Lq .
Interesting properties of 1+q:
(1+q)2 has only 2 square roots
(1+q)x = 1+q doesn't imply x=1 (for example x=q works)
(1+q)x = 0 doesn't imply x=0 (for example x=1-q works)
Base 30, we can choose q1=1, q2=...t1q7f1,
q3=...dcm58b and q4=...eaprnb. In the following list,
we will refer to these as 1, i, j and k.
i2 = j2 = k2 = 1
ij = i/j = j/i = k
ik = i/k = k/i = j
jk = j/k = k/j = i
1 has 8 square roots
rLr
has either 0 or 8 square roots
(1+i)2 has only 4 square roots
r*(1+i) has either 0 or 4 square roots
1+i+j+k has only 2 square roots
r*(1+i+j+k) has either 0 or 2 square roots
LQ1:
If Lq Lr
, then
m
Lq
such that 1/m
Lf .
Thus for number bases that aren't prime or a power of a prime, Lf is not a field.
LQ2:
If Lq Lr
, then
m,n
Lq ,
m
0 and n
0 such that mn = 0.
Thus for number bases that aren't prime or a power of a prime, Lf is not an integral domain.
One conclusion from this is that division is not necessarily unique for these number bases within Lq .
© Scott Sherman 1999