We conjecture that the class of frame matroids can be characterized by a sentence in the monadic second-order logic of matroids, and we prove that there is such a characterization for the class of bicircular matroids. The proof does not depend on an excluded-minor characterization.

中文翻译：

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在 Monadic Logic 中定义双圆拟阵

我们推测框架拟阵类可以用拟阵的一元二阶逻辑中的一个句子来刻画，我们证明了双圆拟阵类存在这样的刻画。证明不依赖于排除次要特征。