20M14 5 20M10 3 06B35 1 14H55 1 20M07 1 20M17 1 20M18 1 54B20 1 Arf numerical semigroup 1 Commutative semigroup 1 Primary 20M13; Secondary 40A05 1 Weierstrass semigroup 1 \(\rho\)-solid 1 approximation 1 atomic Puiseux monoids 1 bijection 1 elasticity 1 factorization invariants 1 hypersubstitution 1 lattice of partitions 1 numerical monoids 1 numerical semigroup 1 sandwich-semigroup 1 semigroup of filters 1 semigroup of linked upfamilies 1 set of distances 1 sets of lengths 1 sparse numerical semigroup 1 superextension 1 variant 1