Principal subresultant coefficients of two polynomials
Subresultants[poly1, poly2, var]
Subresultants[poly1, poly2, var, Modulus -> p]
Subresultants[(x - 1)(x - 2) ^ 2(x - 3) ^ 3, (x - 1)(x - 2) ^ 2(x - 4)(x - 5) ^ 2, x]
→ {0, 0, 0, -64, 44, -5, 1}Subresultants[2x ^ 7 + 3x ^ 3 - 7x + 1, 3x ^ 5 - 17x + 21, x]
→ {273612691817, 68946901, 1299537, 16641, 0, 9}Subresultants[(x - 1) ^ 2(x - 2)(x - 3), (x - 1)(x - 4) ^ 2, x]
→ {0, 36, 11, 1}