Harvey Friedman’s problem Ind-group Mathematics & science Research & information: general Weyl algebra automorphisms adaptive resource additively exact algorithm affine algebraic geometry affine spaces algorithmic unsolvability almost disjoint forcing almost-disjoint forcing automorphisms chain-cycle graph definability definability of definable deformation quantization discrete optimization elementary equivalence embeddability of varieties exact algorithm finitely presented algebraic systems first order rigidity free associative algebras generic models graph of degree 2 graph transformation infinite prime number isotypic algebras minimization of total cost