M 系列について考える必要に迫られたので、理解したことをここに記しておく。本記事では周期の導出，論理回路による並列計算について記す。本記事は拙著「LFSRによる擬似ランダムビット列生成」（☆1）とは異なるアプローチをとる。☆1 ではビット列の生成を、 Laurent 級数を求める為の無限に続く割り算の商と結び付けたが、本記事では余りに結び付ける。
\[
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