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              "value": "This algorithm works only for systems with banded matrix A plus a correction term U @ V.T, where the matrix U @ V.T gives upper right and lower left block of A The system is solved with the following steps:     1.  New systems of linear equations are constructed:         A @ z_i = u_i,         u_i - column vector of U,         i = 1, ..., k - 1     2.  Matrix Z is formed from vectors z_i:         Z = [ z_1 | z_2 | ... | z_{k - 1} ]     3.  Matrix H = (1 + V.T @ Z)^{-1}     4.  The system A' @ y = b is solved     5.  x = y - Z @ (H @ V.T @ y) Also, "
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