21377

Properties

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has period 71.at n=16A020410
• Least prime in A001359 (lesser of twin primes) such that the distance (A053319) to the next twin is 6*n.at n=18A052350
• Smallest prime that is obtained by placing digits on both sides of the n-th prime. Or smallest prime that encompasses the n-th prime.at n=32A075595
• Primes which are the sum of three positive 4th powers.at n=31A085318
• Smallest prime p such that both (p-1)/2^(2n-1) and 2^(2n-1)*p+1 are primes.at n=3A085832
• a(n) = A085956(3n+1).at n=21A086362
• Primes p such that 128p+1 and (p-1)/128 are both prime.at n=0A086477
• Primes A005382(n) + A005384(n) - 1 with a twin prime A005382(n) + A005384(n) + 1.at n=28A099109
• Primes of the form 256n+129.at n=23A105130
• Primes of the form 48k+17 generated recursively. Initial prime is 17. General term is a(n)=Min {p is prime; p divides (2Q)^8 + 1; Mod[p,48]=17}, where Q is the product of previous terms in the sequence.at n=3A125042
• Primes p of the form a^4+b^4+c^4 with a,b,c>=1 such that a^2+b^2+c^2 is another prime < p.at n=24A126117
• Lesser of twin primes (p,q=p+2) such that p*q-p-q and p*q+p+q are primes.at n=3A126334
• Prime numbers that are the sum of three distinct positive fourth powers.at n=19A126657
• Primes p such that p*q-p-q and p*q+p+q are prime where q=nextprime(p).at n=38A128548
• Primes congruent to 27 mod 61.at n=39A142825
• Coefficients in a q-analog of the function LambertW(-2x)/(-2x) at q=2.at n=4A152557
• Primes such that when they are concatenated with their 10's complement (which also must be prime), the result is a brilliant number.at n=16A168466
• Prime numbers containing the digit string 137.at n=19A190307
• Primes of the form 128*k + 1.at n=39A208177
• Primes that are sum of both three and five consecutive primes.at n=29A211170