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Name		Name	Last commit message	Last commit date
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Ahmad J. Masad/Nearest integer to prime(n)^prime(n+1) ÷ prime(n+1)^prime(n)		Ahmad J. Masad/Nearest integer to prime(n)^prime(n+1) ÷ prime(n+1)^prime(n)
Albert Böschow/Numbers k where phi(k) divides k - 3		Albert Böschow/Numbers k where phi(k) divides k - 3
Alex Costea/Integers k divided by log2(k) are almost integers		Alex Costea/Integers k divided by log2(k) are almost integers
Alex Ratushnyak		Alex Ratushnyak
Alexander Adamchuk		Alexander Adamchuk
Alexander R. Povolotsky		Alexander R. Povolotsky
Altug Alkan		Altug Alkan
Amarnath Murthy		Amarnath Murthy
Amiram Eldar		Amiram Eldar
Antti Karttunen/Numbers k such that derivative(sigma(k)) = k		Antti Karttunen/Numbers k such that derivative(sigma(k)) = k
Arkadiusz Wesolowski/Numbers k such that phi(binomial(k,2)) is a power of 2		Arkadiusz Wesolowski/Numbers k such that phi(binomial(k,2)) is a power of 2
Arsen Vardanyan/Numbers k such that 29^k - 2 is prime		Arsen Vardanyan/Numbers k such that 29^k - 2 is prime
Artsiom Palkounikau/Smallest k such that 2^(3*2^n) - k is a safe prime		Artsiom Palkounikau/Smallest k such that 2^(3*2^n) - k is a safe prime
Artur Jasinski		Artur Jasinski
Benoit Cloitre		Benoit Cloitre
Bernard Schott		Bernard Schott
Bodo Zinser/Numbers which when chopped into one, two or more parts, added and squared result in the same number		Bodo Zinser/Numbers which when chopped into one, two or more parts, added and squared result in the same number
Brad Clardy/Number of Fermat pseudoprimes between 2^n and 2^(n+1) that are not Carmichael numbers		Brad Clardy/Number of Fermat pseudoprimes between 2^n and 2^(n+1) that are not Carmichael numbers
Chai Wah Wu		Chai Wah Wu
Charles Marsden/Smallest index k such that the k-th prime number in base-2 contains the n-th Fibonacci number in base-2 as a contiguous substring		Charles Marsden/Smallest index k such that the k-th prime number in base-2 contains the n-th Fibonacci number in base-2 as a contiguous substring
Charles R Greathouse IV		Charles R Greathouse IV
Charles T. Le/Number of prime factors of 1+(n!)^2 (with multiplicity)		Charles T. Le/Number of prime factors of 1+(n!)^2 (with multiplicity)
Charlie Neder/Modulo p is strictly increasing over the first n primes		Charlie Neder/Modulo p is strictly increasing over the first n primes
Cino Hilliard/Numbers n such that n^n + 10 is prime		Cino Hilliard/Numbers n such that n^n + 10 is prime
Clark Kimberling/Least k such that exp(log(1) - log(2)*n) > (exp((lngamma(k+1) + k) - (log(sqrt(2*Pi)) + log(k)*(k + 0.5))) - 1)		Clark Kimberling/Least k such that exp(log(1) - log(2)*n) > (exp((lngamma(k+1) + k) - (log(sqrt(2*Pi)) + log(k)*(k + 0.5))) - 1)
Claude H. R. Dequatre/Numbers k such that tau(k) + tau(Fibonacci(k)) is in A001248, where tau(k) is the number of divisors of k		Claude H. R. Dequatre/Numbers k such that tau(k) + tau(Fibonacci(k)) is in A001248, where tau(k) is the number of divisors of k
Claudio Meller		Claudio Meller
Colin Barker		Colin Barker
Ctibor O. Zizka/Sum of floor(n^2 over k^2)		Ctibor O. Zizka/Sum of floor(n^2 over k^2)
César Aguilera/Perfect numbers pseudo-relation		César Aguilera/Perfect numbers pseudo-relation
Daniel Hoya/Fibonacci Lucas primes		Daniel Hoya/Fibonacci Lucas primes
Daniel Lignon/Composite numbers for which the harmonic mean of proper divisors is an integer		Daniel Lignon/Composite numbers for which the harmonic mean of proper divisors is an integer
Daniel Suteu		Daniel Suteu
Darío Clavijo/Numbers k such that k! + k^3 + 1 is prime		Darío Clavijo/Numbers k such that k! + k^3 + 1 is prime
David James Sycamore		David James Sycamore
Derek Orr		Derek Orr
Donovan Johnson/Smallest number m such that sigma(m) has exactly n distinct prime factors		Donovan Johnson/Smallest number m such that sigma(m) has exactly n distinct prime factors
Eder Vanzei/Primes of the form concatenation(n (once), n-1 (twice), n-2 (3 times), ..., 1 (n times))		Eder Vanzei/Primes of the form concatenation(n (once), n-1 (twice), n-2 (3 times), ..., 1 (n times))
Eduard Roure Perdices		Eduard Roure Perdices
Elliott Line/Pascal-Fibonacci triangle		Elliott Line/Pascal-Fibonacci triangle
Erich Friedman		Erich Friedman
Falcon Shapiro		Falcon Shapiro
Farideh Firoozbakht		Farideh Firoozbakht
Felix Fröhlich		Felix Fröhlich
Fernando Solanet Mayou/a(n) is the smallest number that is (zeroless) pandigital in all bases 2 <= k <= n		Fernando Solanet Mayou/a(n) is the smallest number that is (zeroless) pandigital in all bases 2 <= k <= n
G. L. Honaker, Jr.		G. L. Honaker, Jr.
Gionata Neri		Gionata Neri
Giorgos Kalogeropoulos		Giorgos Kalogeropoulos
Giovanni Resta		Giovanni Resta
Gonzalo Martínez		Gonzalo Martínez
Greg Dresden/Least k such that the denominators of continued fraction convergents for sqrt(k) match the first n Fibonacci numbers		Greg Dresden/Least k such that the denominators of continued fraction convergents for sqrt(k) match the first n Fibonacci numbers
Gus Wiseman		Gus Wiseman
Hans Havermann/Least k such that the decimal representation of 2^k contains all possible n-digit strings		Hans Havermann/Least k such that the decimal representation of 2^k contains all possible n-digit strings
Howard Berman/Numbers m such that sigma(m) is a perfect number		Howard Berman/Numbers m such that sigma(m) is a perfect number
Hugo Pfoertner		Hugo Pfoertner
Ilya Gutkovskiy		Ilya Gutkovskiy
Irina Gerasimova/Numbers n such that Omega(n) = Omega(2^n + 1), where Omega = A001222 is the number of prime factors counted with multiplicity		Irina Gerasimova/Numbers n such that Omega(n) = Omega(2^n + 1), where Omega = A001222 is the number of prime factors counted with multiplicity
Ivan N. Ianakiev/Intersection of A000330 and A086849		Ivan N. Ianakiev/Intersection of A000330 and A086849
J. Lowell		J. Lowell
J. M. Bergot		J. M. Bergot
J.W.L. (Jan) Eerland		J.W.L. (Jan) Eerland
Jacques Tramu/First odd prime in the (n-th)-order Fibonacci sequence Fn		Jacques Tramu/First odd prime in the (n-th)-order Fibonacci sequence Fn
James S. DeArmon/a(n) is the number of prime quadruples of the form {p, p+2, p+6, p+12} with p < 10^n		James S. DeArmon/a(n) is the number of prime quadruples of the form {p, p+2, p+6, p+12} with p < 10^n
Jaroslav Krizek		Jaroslav Krizek
Jason Earls		Jason Earls
Jean-Marc Rebert		Jean-Marc Rebert
Jeff Burch/Least k such that the period of continued fraction for sqrt(k) has at least n successive 1s		Jeff Burch/Least k such that the period of continued fraction for sqrt(k) has at least n successive 1s
Jeppe Stig Nielsen/Smallest base-2 even pseudoprime (A006935) with exactly n prime factors, or 0 if no such number exists		Jeppe Stig Nielsen/Smallest base-2 even pseudoprime (A006935) with exactly n prime factors, or 0 if no such number exists
Jianing Song		Jianing Song
Jinyuan Wang		Jinyuan Wang
Jon E. Schoenfield		Jon E. Schoenfield
Jonathan Sondow/Largest prime factor of numerator of Sum_{k=0..n} factorial(k)^(-1)		Jonathan Sondow/Largest prime factor of numerator of Sum_{k=0..n} factorial(k)^(-1)
Jonathan Vos Post/a(n) = k is the smallest number such that k^3 + 1 has exactly n distinct prime factors		Jonathan Vos Post/a(n) = k is the smallest number such that k^3 + 1 has exactly n distinct prime factors
Joseph Biberstine/Sum of remainders of the n-th prime mod k, for k = 1..n		Joseph Biberstine/Sum of remainders of the n-th prime mod k, for k = 1..n
José María Grau Ribas/Numbers n such that phi(n) divides n+1, where phi is Euler's totient function (A000010)		José María Grau Ribas/Numbers n such that phi(n) divides n+1, where phi is Euler's totient function (A000010)
Jud McCranie		Jud McCranie
Julien Peter Benney/Indices of prime Pell numbers		Julien Peter Benney/Indices of prime Pell numbers
Juri-Stepan Gerasimov		Juri-Stepan Gerasimov
Kelvin Voskuijl		Kelvin Voskuijl
Kevin Batista/Smallest strong pseudoprime to base 2 with n prime factors		Kevin Batista/Smallest strong pseudoprime to base 2 with n prime factors
Kevin P. Thompson		Kevin P. Thompson
Kevin Ryde/a(1) = 1 and thereafter a(n) = 2*prime(a(n-1))		Kevin Ryde/a(1) = 1 and thereafter a(n) = 2*prime(a(n-1))
Klaus Brockhaus		Klaus Brockhaus
Labos Elemer		Labos Elemer
Lekraj Beedassy		Lekraj Beedassy
Leroy Quet/Mobius transform of Sum_{k=1..n} tau(k)		Leroy Quet/Mobius transform of Sum_{k=1..n} tau(k)
Lorenzo Sauras Altuzarra/Inverse tetrahedral		Lorenzo Sauras Altuzarra/Inverse tetrahedral
Luis H. Gallardo/Number of distinct prime factors of g(p) = (p^p-1) over (p-1) where p = prime(n)		Luis H. Gallardo/Number of distinct prime factors of g(p) = (p^p-1) over (p-1) where p = prime(n)
M. F. Hasler		M. F. Hasler
M. Farrokhi D. G./Primes p such that (2^(p-1)*(p+1) - 1) div p is prime		M. Farrokhi D. G./Primes p such that (2^(p-1)*(p+1) - 1) div p is prime
Maheswara Rao Valluri/Glitch primes		Maheswara Rao Valluri/Glitch primes
Manuel Valdivia/Smallest prime p such that 2^(p-1) == 1 mod prod a(k)		Manuel Valdivia/Smallest prime p such that 2^(p-1) == 1 mod prod a(k)
Marco Ripà		Marco Ripà
Marius A. Burtea/Triangular numbers whose arithmetic derivative is also a triangular number		Marius A. Burtea/Triangular numbers whose arithmetic derivative is also a triangular number
Matthew Campbell/a(n) is obtained by applying the map k -> composite(k) n times, starting at n		Matthew Campbell/a(n) is obtained by applying the map k -> composite(k) n times, starting at n
Max Alekseyev		Max Alekseyev
Max Z. Scialabba/Least number k such that sigma(sigma(k) * k) > n * sigma(k) * k		Max Z. Scialabba/Least number k such that sigma(sigma(k) * k) > n * sigma(k) * k
Metin Sariyar		Metin Sariyar
Michael S. Branicky/Smallest palindrome with exactly n distinct prime factors		Michael S. Branicky/Smallest palindrome with exactly n distinct prime factors
Michel Lagneau		Michel Lagneau
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