Table of contents : On the difficulty of finding reliable witnesses....Pages 1-16 Density computations for real quadratic 2-class groups....Pages 17-17 Lattice sieving and trial division....Pages 18-27 A subexponential algorithm for discrete logarithms over the rational subgroup of the Jacobians of large genus hyperelliptic curves over finite fields....Pages 28-40 Computing rates of growth of division fields on CM Abelian varieties....Pages 41-41 Algorithms for CM-Fields....Pages 42-42 Schoof's algorithm and isogeny cycles....Pages 43-58 Integer points on rational elliptic curves....Pages 59-59 Counting the number of points on elliptic curves over finite fields of characteristic greater than three....Pages 60-70 Straight-line complexity and integer factorization....Pages 71-79 Decomposition of algebraic functions....Pages 80-92 A new modular interpolation algorithm for factoring multivariate polynomials....Pages 93-107 The function field sieve....Pages 108-121 Heegner point computations....Pages 122-133 Computing the degree of a modular parametrization....Pages 134-142 Galois representations from the cohomology of SL(3,ℤ)....Pages 143-143 An analysis of the Gaussian algorithm for lattice reduction....Pages 144-158 A fast variant of the Gaussian reduction algorithm....Pages 159-159 Reducing lattice bases by means of approximations....Pages 160-168 Analysis of a left-shift binary GCD algorithm....Pages 169-183 The complexity of greatest common divisor computations....Pages 184-193 Explicit formulas for units in certain quadratic number fields....Pages 194-208 Factorization of polynomials over finite fields in subexponential time under GRH....Pages 209-219 On orders of optimal normal basis generators....Pages 220-220 Computing in the jacobian of a plane algebraic curve....Pages 221-233 Under the assumption of the Generalized Riemann Hypothesis verifying the class number belongs to NP ∩ co-NP....Pages 234-247 Calculating the class number of certain Hilbert class fields....Pages 248-248 Efficient checking of computations in number theory....Pages 249-249 Constructing elliptic curves with given group order over large finite fields....Pages 250-263 Computing π(x), M(x) and Ψ(x)....Pages 264-264 On some applications of finitely generated semi-groups....Pages 265-279 Improved incremental prime number sieves....Pages 280-288 Polynomial time algorithms for discrete logarithms and factoring on a quantum computer....Pages 289-289 On dispersion and Markov constants....Pages 290-290 Open problems in number theoretic complexity, II....Pages 291-322