21961

Properties

Appears in sequences

• Next prime after n^3.at n=28A014220
• Numbers whose least quadratic nonresidue (A020649) is 17.at n=16A025026
• Smallest prime that is simultaneously of forms x^2 + m*y^2 for m = 1, ..., n.at n=12A028372
• Denominators of continued fraction convergents to sqrt(739).at n=10A042423
• Primes with 17 as smallest positive primitive root.at n=21A061329
• Sums of groups in A075635.at n=32A075636
• Balanced primes of order four.at n=22A082079
• Primes in A003154.at n=31A083577
• Smallest prime ending in prime(n) and == 1 (mod prime(n)), or 0 if no such prime exists.at n=17A096069
• a(n) = A000040(A096480(n)).at n=30A096481
• Odd numbers n for which 17 is the smallest i (>= 1) with Jacobi symbol J(i,n) getting either a value 0 or -1.at n=27A112077
• Primes p such that their cubes are pandigital.at n=15A124629
• Primes q of the form a^3+b^2, such that p =A130467(n)= a^2+b^3 is prime and smaller than q; p < q ; b < a.at n=12A130468
• Prime numbers p such that p +- ((p-1)/6) are primes.at n=24A137724
• E.g.f.: A(x) = exp(x*A(x)^2*exp(x^2*A(x)^4*exp(x^3*A(x)^6*exp(x^4*A(x)^8*exp(...))))), an infinite power tower.at n=5A141357
• a(n) is the smallest prime x such that x^2-n! is also prime.at n=11A143933
• Least number expressible as a^2 + k b^2 with positive integers a,b, for each k=1,...,n.at n=12A155715
• Primes that can be written as a sum of a positive square and a positive cube in more than one way.at n=37A162930
• Integers k such that A166100(k)/A005408(k) is not an integer.at n=32A166101
• Primes of the form x^2 + 18480*y^2.at n=4A173274