Mathematics Problem Archive
O21 — Discrete logarithms modulo a prime
v1.3 research notesGiven a prime $p$ and elements $g,b$ with $b$ in the subgroup generated by $g$, can an exponent $x$ satisfying $g^x\equiv b\pmod p$ be found in determ...
O22a — Discrete logarithms modulo a composite
v1.3 research notesGiven $g,b,n$ such that $g^x\equiv b\pmod n$ has a solution, can such an exponent $x$ be found in deterministic polynomial time?...
O22b — Factoring from composite discrete logarithms
v1.3 research notesIs complete integer factorization deterministically polynomial-time reducible to discrete logarithms modulo composites?...
O23 — Factoring from Euler's totient
v1.3 research notesIs complete integer factorization deterministically polynomial-time reducible to computing $\varphi(n)$?...
O24 — Finding a point on an elliptic curve
v1.3 research notesGiven $a,b$ and a prime $p$ with nonsingular curve $y^2=x^3+ax+b$, can a point on the curve modulo $p$ be found in deterministic polynomial time?...
O25 — Solving binary quadratic congruences
v1.3 research notesGiven $k,m,n$ with odd $n$ and $\gcd(km,n)=1$, can integers $x,y$ satisfying $x^2-ky^2\equiv m\pmod n$ be found in deterministic polynomial time?...
O26 — Discrete logarithm versus Diffie–Hellman key distribution
v1.3 research notesIs discrete logarithm modulo a prime randomized polynomial-time reducible to computing $g^{xy}$ from $g,g^x,g^y$?...
O27 — Elliptic curves of prescribed order
v1.3 research notesGiven a prime $p$ and $n$, can one construct in deterministic polynomial time an elliptic curve over $\mathbb{F}_p$ having exactly $n$ points whenever...
O28 — Discrete logarithms in elliptic-curve groups
v1.3 research notesGiven an elliptic curve over $\mathbb{F}_p$ and points $P,Q$ such that $P=nQ$ for some $n$, can such an $n$ be found in deterministic polynomial time?...
O29 — NP-hardness of exact shortest vector
v1.3 research notesFor a full-rank integer lattice, is finding a nonzero vector of minimum Euclidean norm NP-hard?...
O30 — Polynomial-factor lattice approximation
v1.3 research notesDoes there exist a constant $c$ for which one can find in deterministic polynomial time a nonzero lattice vector of length at most $n^c$ times the min...
O31 — Order of a polynomial's Galois group
v1.3 research notesGiven $f\in\mathbb{Q}[x]$, can the degree of its splitting field, equivalently the order of its Galois group, be computed in deterministic polynomial ...
O32 — Class numbers of imaginary quadratic orders
v1.3 research notesGiven $d\in\mathbb{N}$, can the class number $h(-d)$ of binary quadratic forms of discriminant $-d$ be computed in deterministic polynomial time?...
O33a — NP-hardness of binary quadratic Diophantine solvability
v1.3 research notesUnder the promise that $b^2-4ac$ is not a square, is deciding whether $ax^2+bxy+cy^2+dx+ey+f=0$ has an integral solution NP-hard?...
O33b — Randomized NP-hardness of binary quadratic Diophantine solvability
v1.3 research notesIs the same binary quadratic Diophantine solvability problem NP-hard under randomized reductions?...
O34 — Solvability of the negative Pell equation
v1.3 research notesCan one decide in deterministic polynomial time whether $x^2-dy^2=-1$ has an integral solution?...
O35 — Greatest common divisors in NC
v1.3 research notesCan $\gcd(a,b)$ be computed in the parallel complexity class $NC$?...
O36 — Integer multiplication in linear bit complexity
v1.3 research notesCan two positive integers $a,b$ be multiplied using $O(\log(ab))$ bit operations?...
Absolute bounds for rational Diophantine tuples
v1.3 research notesIs there an absolute upper bound for the size of a rational Diophantine $m$-tuple, a set of nonzero rationals for which the product of every two disti...
Exceptional parameters without D(n)-quadruples
v1.3 research notesFor each $n\in\{-3,3,5,8,12,20\}$, prove that no set of four distinct positive integers has property $D(n)$, meaning that every pairwise product plus ...
Finiteness of parameters admitting at most two D(n)-quadruples
v1.3 research notesLet $U$ be the set of integers $n\not\equiv2\pmod4$ for which there are at most two distinct $D(n)$-quadruples. Is $U$ finite?...
Finiteness of D(n)-quadruples for nonsquare n
v1.3 research notesFor every nonzero integer $n$ that is not a square, are there only finitely many $D(n)$-quadruples?...
Extremal parameters for D(n)-quintuples
v1.3 research notesDetermine the least positive integer $n_1$ and the greatest negative integer $n_2$ for which a $D(n_i)$-quintuple exists....
Triples having property D(n) for several parameters
v1.3 research notesAre there infinitely many Diophantine triples that are also $D(n)$-triples for three distinct integers $n\ne1$?...
Existence of a rational Diophantine septuple
v1.3 research notesDoes there exist a rational Diophantine septuple, that is, seven nonzero rational numbers whose pairwise products plus $1$ are rational squares?...
Parameters admitting infinitely many rational D(q)-quintuples
v1.3 research notesFor which rational numbers $q$ do there exist infinitely many rational $D(q)$-quintuples?...
Existence of a strong rational Diophantine quadruple
v1.3 research notesDoes there exist a set of four nonzero rational numbers $\{a_1,a_2,a_3,a_4\}$ such that $a_i a_j+1$ is a rational square for every $1\le i,j\le4$, inc...
Degree-only bounds for polynomial D(n)-tuples
v1.3 research notesLet $P_n$ be the supremum of the sizes of nondegenerate polynomial $D(n)$-tuples over $\mathbb{Z}[X]$. Find an upper bound for $P_n$ depending only on...
Problem 1.1
v1.3 research notesLet $f\in\mathbb{Z}[X,Y]$ be a polynomial such that the equation $f(x,y)=0$ has only finitely many solutions $(x,y)\in \mathbb{Z}\times\mathbb{Z}$. Gi...
Conjecture 1.3 — Pillai
v1.3 research notesLet $k$ be a positive integer. The equation $$ x^p-y^q=k, $$ where the unknowns $x$, $y$, $p$ and $q$ take integer values, all $\ge 2$, has only finit...
Conjecture 1.4 — Shorey
v1.3 research notesThere exists a positive number $C$ which depends only on $L$ and $H$ with the following property. Let $m$, $x$ and $y$ be rational integers with $m\ge...
Conjecture 1.5
v1.3 research notesLet $k\ge 2$ be an integer and $\alpha_1,\ldots,\alpha_n$ be non-zero elements in a field $K$ of zero characteristic, such that no quotient $\alpha_i/...
Conjecture 1.7
v1.3 research notesIf there is no prime in the interval $[n+1,n+k]$, then the product $(n+1)\cdots(n+k)$ has at least $k$ distinct prime divisors....
Conjecture 1.8 — Langevin
v1.3 research notesGiven an increasing sequence $n_1<n_2<\cdots<n_k$ of positive integers such that $n_1,n_2,\ldots,n_k$ are multiplicatively dependent, there exists a p...
Conjecture 1.9
v1.3 research notesFix a positive integer $m$ for which the equation $$ m^2 + m_1^2 + m_2^2 = 3 mm_1m_2 $$ has a solution in positive integers $(m_1,m_2)$ with $0<m_1\le...
Conjecture 2.2 — Erdős-Woods
v1.3 research notesThere exists a positive integer $k$ such that, for $m$ and $n$ positive integers, the conditions $$ R(m+i)=R(n+i)\quad (i=0,\ldots,k-1) $$ imply $m=n$...
Conjecture 2.3 — Erdős–Dressler
v1.3 research notesIf $a$ and $b$ are two positive integers with $a<b$ and $R(a)=R(b)$ then there is a prime $p$ with $a< p< b$....
Conjecture 2.4 — Philippon
v1.3 research notesThere exist real numbers $\varepsilon$, $\alpha$ and $\beta$ with $0<\varepsilon<1/2$, $\alpha\ge 1$ and $\beta\ge 0$, and a positive integer $B$, suc...
Conjecture 2.5 — Lang-Waldschmidt
v1.3 research notesFor any $\varepsilon>0$, there exists a constant $C(\varepsilon)>0$ such that, for any nonzero rational integers $a_1,\ldots,a_m$, $b_1,\ldots,b_m$ wi...
Conjecture 2.6
v1.3 research notesFor any $\varepsilon>0$, there is a constant $C(\varepsilon)>0$ such that, for any positive integers $x$, $y$, $p$, $q$ satisfying $x^p\not= y^q$, the...
Conjecture 2.7 — Hall
v1.3 research notesIf $x$ and $y$ are positive integers with $y^2\not=x^3$, then $$ |y^2-x^3|\ge C\max\{y^2,x^3\}^{1/6}. $$...
Conjecture 2.12
v1.3 research notesLet $\theta$ be real algebraic number of degree at least $3$. Then inequality (2.11) has infinitely many solutions in integers $p$ and $q$ with $q>0$ ...
Conjecture 2.14 — Mahler
v1.3 research notesThere exists an absolute constant $c>0$ such that $$ \Vert \log a\Vert>a^{-c} $$ for all integers $a\ge 2$....
Conjecture 2.15 — Mahler
v1.3 research notesLet $(\varepsilon_n)_{n\ge 0}$ be a sequence of elements in $\{0,1\}$. Assume that the real number $$ \sum_{n\ge 0}\varepsilon_n 3^{-n} $$ is irration...
Conjecture 3.2 — Roy
v1.3 research notesLet $k$ be a positive integer, $y_1,\ldots,y_k$ complex numbers which are linearly independent over $\mathbb{Q}$, $\alpha_1,\ldots,\alpha_k$ nonzero c...
Conjecture 3.3 — Algebraic Independence of Logarithms of Algebraic Numbers
v1.3 research notesLet $\lambda_1,\ldots, \lambda_n$ be $\mathbb{Q}$-linearly independent complex numbers. Assume that the numbers $e^{\lambda_1},\ldots,e^{\lambda_n}$ a...
Conjecture 3.4 — Strong Four Exponentials Conjecture
v1.3 research notesLet $x_1,x_2$ be two $\overline{\mathbb{Q}}$-linearly independent complex numbers and $y_1,y_2$ be also two $\overline{\mathbb{Q}}$-linearly independe...
Conjecture 3.5 — Strong Five Exponentials Conjecture
v1.3 research notesLet $x_1, x_2$ be two $\mathbb{Q}$-linearly independent complex numbers and $y_1, y_2$ be also two $\mathbb{Q}$-linearly independent complex numbers. ...
Conjecture 3.6 — Roy
v1.3 research notesFor any $4\times 4$ skew-symmetric matrix $\mathrm{M}$ with entries in $\mathcal{L}$ and rank $\le 2$, either the rows of $\mathrm{M}$ are linearly de...
Conjecture 3.8 — Gel’fond
v1.3 research notesThe two numbers $$ \log\alpha\quad\text{and}\quad \alpha^\beta $$ are algebraically independent over $\mathbb{Q}$....