an ideal, generated by the permanents of the n by n subpermanents of M
Description
The permanent of a square matrix N has the Laplace transform similar to the Laplace transform of the determinant of N: but all signs are positive. Permanents are used in combinatorics and in probability. They are computationally difficult.
i1 : R = ZZ[a..f];
i2 : M = genericMatrix(R,a,2,3)
o2 = | a c e |
| b d f |
2 3
o2 : Matrix R <--- R
i3 : permanents(2,M)
o3 = ideal (b*c + a*d, b*e + a*f, d*e + c*f)
o3 : Ideal of R