赵日天4 years ago

It’s still unknown whether there are infinitely many number fields of class number 1.

So I decided to investigate more number fields uncovered in the Wikipedia article.

Conjecture: There exists , such that for sufficiently large degree, the probability for a randomly-chosen Littlewood polynomial to generate a class-1 field is larger than .

The way to randomly choose Littlewood polynomials is up to interpretation: it’s not sure how one could avoid reducible polynomials.

Computational results:

DegreeNumber of fields with class number > 1
≤90
102
110
124
13 8
14 45
15 46
16 135
17 212
18 452
19 766
20 1122

*Different Littlewood polynomials could generate the same field, e.g. and , so there’s a difference between counting the number of polynomials and the number of fields.

 

  • .

(Requires xn+x+1 to be reducible, i.e. x≠2 mod 3 unless x=2)

All computed cases have class number 1. The s in the cases are up to 70 except 69.

Remark: To compute the class number, one can use the Dedekind L function(hard, since the field is generally non-abelian) and the regulator.

An empirical formula for the regulator: .

Computational results:

nREGULATORClass number
211
30.3822450858400361
40.3373778035715621
60.6585292088583491
71.288917143238541
94.587563751162171
107.348137904948271
1243.01249970553491
13117.9171983655521
15548.8741394482631
161339.394664303481
189114.458675143491
1940842.92897439281
21312816.60148773111
22685583.04627769661
249163307.1750320531
2536955124.389604241
27314436524.83395561
28832511028.30940911
3011086740597.2235951
3160402933903.837121
33794597544869.87351
341946991838336.1071
3642496810214502.41
37232694775426930.71
391954406735071007.51
409483736502678452.01
421.22671527299859e171
438.65244826944888e171
451.81327874783812e191
465.12503081683112e191
481.44282942692530e211
498.96333031274895e211
511.39007666627654e231
525.53110242701541e231
541.37500354842092e251
555.98268106963661e251
572.10334315815568e271
587.03923877738823e271
602.40946814771980e291
611.45431932648604e301
632.90399143790153e311
641.36851987479281e321
663.34395953400078e331
672.38125833961797e341
69??
702.97700584009327e361