Redheffer matrix

In mathematics, a Redheffer matrix, studied by Redheffer (1977), is a (0,1) matrix whose entries a_ij are 1 if i divides j or if j = 1; otherwise, a_ij = 0.

The determinant of the nxn square Redheffer matrix is given by the Mertens function M(n).

The matrix below is the 12 × 12 Redheffer matrix.

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