macsyma on Tue, 27 Aug 2019 07:39:12 +0200


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Re: the minimal polynomial over the composite field


Thank you, Bill.

Your method uses galoisinit(), but at least for my purposes, 
the speed of it is not enough.
For example, the timing for only galoisinit(nfsplitting()) are


? for(n=2,16,galoisinit(nfsplitting(x^n-2)));
time = 4,165 ms.

and


? galoisinit(nfsplitting(x^17-2));
time = 33min, 16,082 ms.


On the other hand, the timing of the whole processing by my code are


http://macsyma.starfree.jp/maxima/post20190827.txt


and


[17] x^17-2 
0 
1 
using a factor (-51272*c17^15)-12104*c17^14-11016*c17^13-60996*c17^12
-7616*c17^11-12342*c17^10-37128*c17^9+12376*c17^8-12410*c17^7
-17136*c17^6+36244*c17^5-13736*c17^4-12648*c17^3+26520*c17^2-24752*c17+A^17-12376 
over the cyclotomic_17

272 17 [17] 4.641 0.011 
[[A-e1,A],
 [e1^17-51272*c17^15-12104*c17^14-11016*c17^13-60996*c17^12-7616*c17^11
       -12342*c17^10-37128*c17^9+12376*c17^8-12410*c17^7-17136*c17^6
       +36244*c17^5-13736*c17^4-12648*c17^3+26520*c17^2-24752*c17-12376,e1],
 [c17^16+c17^15+c17^14+c17^13+c17^12+c17^11+c17^10+c17^9+c17^8+c17^7+c17^6
        +c17^5+c17^4+c17^3+c17^2+c17+1,c17]]

Evaluation took 0.1550 seconds (4.6530 elapsed) using 73.874 MB.

macsyma