49921

Properties

Appears in sequences

• Primes that remain prime through 3 iterations of function f(x) = 3x + 8.at n=32A023279
• Numbers whose least quadratic nonresidue (A020649) is 19.at n=18A025027
• Primes with 23 as smallest positive primitive root.at n=15A061335
• Antidiagonal sums of table A083044.at n=19A083046
• Smallest prime such that n*k(n)^2+n*k(n)+1 is a prime > (n-1)*k(n-1)^2+(n-1)*k(n-1)+1 with k(n)>1 or 0 if n=4 as no prime possible.at n=31A104995
• Primes of the form 512n+257.at n=19A105131
• Odd numbers n for which 19 is the smallest i (>= 1) with Jacobi symbol J(i,n) getting either a value 0 or -1.at n=30A112078
• Anti-elite primes: a prime number p is called anti-elite if only a finite number of Fermat numbers 2^(2^n)+1 are quadratic non-residues mod p.at n=15A128852
• Primes of the form 3*m^2 - 2.at n=19A201715
• Primes of the form 8n^2 - 7.at n=17A201858
• Primes of the form 256*k + 1.at n=37A208178
• Primes of the form 384*k + 1.at n=35A229854
• Number of nX4 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of elements above it or one plus the sum of the elements diagonally to its northwest, modulo 4.at n=4A240268
• T(n,k)=Number of nXk 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest, modulo 4.at n=32A240271
• Number of 5Xn 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest, modulo 4.at n=3A240275
• 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=23A261405
• Primes p congruent to 1 modulo 13 such that x^13 = 2 has a solution modulo p.at n=31A275773
• Number of 2 X 2 matrices with integer entries in [-n,n] that are diagonalizable over the complex numbers.at n=6A338413
• Fold a square sheet of paper alternately vertically to the left and horizontally downwards; after each fold, draw a line along each inward crease; after n folds, the resulting graph has a(n) regions.at n=19A342759
• A sequence of primes starting with p_1 = 2, p_2 = 3, p_3 = 5, p_4 = 11, p_5 = 13, p_6 = 23, such that, for i >= 7, (p_i + 1)/2 divides the product p_1*p_2*...*p_(i-1) of the earlier primes and each prime factor of (p_i-1)/2 is a prime factor of the product p_1*p_2*...*p_(i-1).at n=22A358719