Let ℳ Cf (F) be the set of all column-finite ℕ × ℕ matrices over a field F. The following problem is studied: What elements of ℳ Cf (F) can be expressed as a sum of idempotents? The result states that every element of ℳ Cf (F) can be represented as the sum of 14 idempotents.
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Published in Ukrains’kyi Matematychnyi Zhurnal, Vol. 69, No. 8, pp. 1145–1152, August, 2017.
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Słowik, R. Expressing Infinite Matrices as Sums of Idempotents. Ukr Math J 69, 1333–1340 (2018). https://doi.org/10.1007/s11253-017-1434-3
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DOI: https://doi.org/10.1007/s11253-017-1434-3