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Erdös-Szekeres conjectureErdos; Szekeres✭✭✭0Geometrymdevos
Erdős–Faber–Lovász conjectureErdos; Faber; Lovasz✭✭✭0Graph Theory » Coloring » Vertex coloringJon Noel
Erdős–Straus conjectureErdos; Straus✭✭1Number TheoryACW
Euler-Mascheroni constant✭✭✭0Number Theory » Analytic N.T.Juggernaut
Even vs. odd latin squaresAlon; Tarsi✭✭✭0Combinatoricsmdevos
Every 4-connected toroidal graph has a Hamilton cycleGrunbaum; Nash-Williams✭✭0Graph Theory » Topological G.T.fhavet
Every metamonovalued funcoid is monovaluedPorton✭✭0Topologyporton
Every metamonovalued reloid is monovaluedPorton✭✭0Topologyporton
Every prism over a 3-connected planar graph is hamiltonian.Kaiser; Král; Rosenfeld; Ryjácek; Voss✭✭0Graph Theory » Basic G.T. » Cyclesfhavet
Exact colorings of graphsErickson✭✭0Graph TheoryMartin Erickson
Exponential Algorithms for KnapsackLipton✭✭1Theoretical Comp. Sci. » Algorithmsdick lipton
Extension complexity of (convex) polygons✭✭0Geometry » PolytopesDOT
Extremal $4$-Neighbour Bootstrap Percolation in the HypercubeMorrison; Noel✭✭0CombinatoricsJon Noel
Extremal problem on the number of tree endomorphismZhicong Lin✭✭1Graph Theory » Extremal G.T.shudeshijie
Faithful cycle coversSeymour✭✭✭0Graph Theory » Basic G.T. » Cyclesmdevos
Fat 4-polytopesEppstein; Kuperberg; Ziegler✭✭✭0Geometry » Polytopesmdevos
Few subsequence sums in Z_n x Z_nBollobas; Leader✭✭0Number Theory » Combinatorial N.T.mdevos
Finding k-edge-outerplanar graph embeddingsBentz✭✭0Graph Theoryjcmeyer
Finite entailment of Positive Horn logicMartin✭✭0Logic » Finite Model TheoryLucSegoufin
Finite Lattice Representation Problem✭✭✭✭0Algebrawilliamdemeo
Fixed-point logic with countingBlass✭✭0Logic » Finite Model Theorydberwanger
Forcing a $K_6$-minorBarát ; Joret; Wood✭✭0Graph Theory » Basic G.T. » MinorsDavid Wood
Forcing a 2-regular minorReed; Wood✭✭1Graph Theory » Basic G.T. » MinorsDavid Wood
Fractional HadwigerHarvey; Reed; Seymour; Wood✭✭1Graph TheoryDavid Wood
Frankl's union-closed sets conjectureFrankl✭✭0Graph Theory » Hypergraphstchow
Friendly partitionsDeVos✭✭0Graph Theory » Basic G.T.mdevos
Frobenius number of four or more integers✭✭1Number Theory » Combinatorial N.T.maxal
Funcoidal products inside an inward reloidPorton✭✭0Topologyporton
Fundamental group torsion for subsets of Euclidean 3-spaceAncient/folklore✭✭0Topologyrybu
F_d versus F_{d+1}Krajicek✭✭✭0Logiczitterbewegung
Gao's theorem for nonabelian groupsDeVos✭✭0Number Theory » Combinatorial N.T.mdevos
General position subsetsGowers✭✭0GeometryDavid Wood
Generalised Empty Hexagon ConjectureWood✭✭1GeometryDavid Wood
Generalized path-connectedness in proximity spacesPorton✭✭0Topologyporton
Geodesic cycles and Tutte's TheoremGeorgakopoulos; Sprüssel✭✭1Graph Theory » Basic G.T. » CyclesAgelos
Giuga's Conjecture on PrimalityGiuseppe Giuga✭✭0Number Theoryprinceps
Goldbach conjectureGoldbach✭✭✭✭0Number Theory » Additive N.T.Benschop
Goldberg's conjectureGoldberg✭✭✭0Graph Theory » Coloring » Edge coloringmdevos
Good Edge LabelingsAraújo; Cohen; Giroire; Havet✭✭0Graph Theory » Coloring » LabelingDOT
Graham's conjecture on tree reconstructionGraham✭✭0Graph Theory » Basic G.T.mdevos
Graph product of multifuncoidsPorton✭✭0Topologyporton
Graphs of exact colorings✭✭0Algebrasabisood
Graphs with a forbidden induced tree are chi-boundedGyarfas✭✭✭0Graph Theory » Coloring » Vertex coloringmdevos
Growth of finitely presented groupsAdyan✭✭✭0Group Theorymdevos
Grunbaum's ConjectureGrunbaum✭✭✭0Graph Theory » Topological G.T. » Coloringmdevos
Half-integral flow polynomial valuesMohar✭✭0Graph Theory » Algebraic G.T.mohar
Hamilton cycle in small d-diregular graphsJackson✭✭0Graph Theory » Directed Graphsfhavet
Hamilton decomposition of prisms over 3-connected cubic planar graphsAlspach; Rosenfeld✭✭0Graph Theory » Basic G.T. » Cyclesfhavet
Hamiltonian cycles in line graphsThomassen✭✭✭0Graph Theory » Basic G.T. » CyclesRobert Samal
Hamiltonian cycles in line graphs of infinite graphsGeorgakopoulos✭✭0Graph Theory » Infinite GraphsRobert Samal

Imp.¹: Importance (Low ✭, Medium ✭✭, High ✭✭✭, Outstanding ✭✭✭✭)
Rec.²: Recommended for undergraduates.

Note: Resolved problems from this section may be found in Solved problems.

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