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unit, which under certain conditions is the fundamental unit, and are important in studying the Diophantine Equation x. + y3 + z. 3. KEY WORDS ... i, and q i, then solving x. +12Ax. 12 y2 is equivalent to solving -AG4 -2 G3H + 3 H4=-I. (This has ...
Internat. J. Math. & Math. Sci. Vol. 9 No. 4 (1986) 797-800

797

ON THE COMPUTATION OF THE CLASS NUMBERS OF SOME CUBIC FIELDS MANNY SCAROWSKY and ABRAHAM BOYARSKY Department of Mathematics Loyola Campus Concordia University Montreal, Canada H4B IR6

(Received December I0, 1985)

ABSTRACT.

x3+12Ax-12

Class numbers are calculated for cubic fields of the form

A > 0, for

!

and for some other values of

! 17

a

A.

0,

These fields have a known

unit, which under certain conditions is the fundamental unit, and are important in

studying the Diophantine Equation

+ y3 +

x

Class numbers, cubic fields, Diophantine equation.

KEY WORDS AND PHRASES.

12A04, 12A50.

1980 AMS SUBJECT CLASSIFICATION CODES.

I.

3.

z

INTRODUCTION AND SOME THEOREMS. We consider the cubic fields defined by an equation of the form

(I.I) 0, 12 to related is it because is important equation The field defined by this f(x)

A > 0.

where

the Diophantine equation

+ y3 +

x

when

3

z

9a 2 [i].

A

Equation (I.I) is

f(x) is increasing, it defines a real cubic field (with two complex conjugates) with exactly one fundamental unit. Let @ be the real and as

clearly irreducible,

K

+ 12Ax

x

root of (1.1).

D

33

-2

have son

q3.

(3)

p3,

(2)

+ 9).

(16A

Also as and as

< i, we have

0