Putnam 2021 B5
- Session B
Say that an -by- matrix with integer entries is very odd if, for every nonempty subset of , the -by- submatrix has odd determinant. Prove that if is very odd, then is very odd for every .
Curated text Kedlaya Putnam archive. Quoted with source.
Solutions
Human solution Solution 1 by Manjul Bhargava, Kiran Kedlaya and Lenny Ng
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