53881

Properties

Appears in sequences

• Pseudo-squares: a(n) = the least nonsquare positive integer which is 1 mod 8 and is a (nonzero) quadratic residue modulo the first n odd primes.at n=7A002189
• Smallest prime p of form p = 8k+1 such that first n primes (p_1=2, ..., p_n) are quadratic residues mod p.at n=7A002224
• Numbers whose least quadratic nonresidue (A020649) is 23.at n=6A025028
• Primes with 31 as smallest positive primitive root.at n=6A061735
• Primes p such that the differences between the 5 consecutive primes starting with p are (6,4,6,2).at n=10A078963
• Smallest prime p == 1 mod 8 (A007519) and p > prime(n+2) such that p is a quadratic residue mod the first n odd primes 3, 5, 7, 11, ..., prime(n+1), and p is a quadratic non-residue mod prime(n+2).at n=7A096637
• Odd primes which set records for smallest absolute value of a quadratic nonresidue.at n=9A102295
• Odd numbers k for which 23 is the smallest positive i with Jacobi symbol J(i,k) != 1.at n=7A112079
• Base-6 pandigital primes: primes having at least one of each digit 0,1,2,3,4,5 when written in base 6.at n=22A175278
• Primes at which occur records of A205531 and A205535.at n=8A205532
• Smallest nonsquare congruent to a square (mod k^2) for all k = 1..n.at n=18A260709
• Smallest nonsquare congruent to a square (mod k^2) for all k = 1..n.at n=19A260709
• Smallest nonsquare congruent to a square (mod k^2) for all k = 1..n.at n=20A260709
• Smallest nonsquare congruent to a square (mod k^2) for all k = 1..n.at n=21A260709
• Primes p such that the maximal length of a Buchi sequence in Z/pZ is less than the value of A124882 for that prime.at n=7A261404
• Primes p such that the maximal length of a nontrivial N(p)-Hensley sequence mod p is less than the value of A124882 for that prime, where N(p) is the least positive quadratic non-residue mod p.at n=26A261405
• Full autoinsertable primes are such primes that remain prime after all the possible internal autoinsertions, one at a time.at n=20A335271
• Numbers p such that p, 2p-1, 3p-2, 4p-3 are primes.at n=18A336059
• Smallest prime numbers which can be represented as x^2 + h*y^2 with x > 0 for every h in the first n idoneal numbers.at n=28A338088
• Smallest prime numbers which can be represented as x^2 + h*y^2 with x > 0 for every h in the first n idoneal numbers.at n=29A338088