TOPICS
Search

Euclidean Window


The Euclidean window of a nonzero prime ideal p in the ring of integers R of a number field is the set of real weights t>0 for which the multiplicative weighted norm, for a!=0,

 phi_t(a)=|N(a)|(t/(Np))^(v_p(a))
(1)

is a Euclidean function, with phi_t(0)=0 (Cardon 2026). Here N(a) is the field norm, Np is the ideal norm, and v_p(a) is the exponent of p in the principal ideal aR. A Euclidean function permits division with strictly smaller remainder and has only finitely many distinct values in each bounded interval.

For R=Z[sqrt(14)] and p=(4+sqrt(14))R, the ideal norm is 2. Cardon (2026) proved that the Euclidean window is (sqrt(5),T], where

 T=sqrt(8/(104051sqrt(2)-55617sqrt(7)))=2.2468286690....
(2)

Thus this nonempty window is not open. Cardon (2026) also obtained the integer-valued, completely multiplicative Euclidean function

 f(a)=2^(v_p(a))|N(a)|^6
(3)

for a!=0, with f(0)=0. The usual field norm is not itself a Euclidean function on Z[sqrt(14)].

Cardon (2026) reports ChatGPT and Claude assistance with numerical programming, searches, and calculations.


See also

Euclidean Ring, Prime Ideal

Explore with Wolfram|Alpha

References

Cardon, D. A. "The Exact Euclidean Window of Z[sqrt(14)]." 16 Oct 2026. https://arxiv.org/abs/2610.24309.

Cite this as:

Weisstein, Eric W. "Euclidean Window." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/EuclideanWindow.html

Subject classifications