21089

Properties

Appears in sequences

• Primes whose digits can be arranged in increasing cyclic order - to form a substring of 123456789012345678901234567890...at n=35A068710
• Primes p such that 2*p+1 and ((2*p+1)^2 + 1)/2 = p^2 + (p+1)^2 are primes.at n=26A098717
• The smallest prime p that makes the pair p+/-6n both primes while no other pair of p+/-6k+6*n, 0<k<n both primes.at n=52A139602
• Primes congruent to 26 mod 59.at n=35A142753
• Primes congruent to 44 mod 61.at n=38A142842
• Primes of the form : (p-n)/(n+1)=prime and (n+1)*p+n=prime. n=4.at n=29A152294
• Lesser of two consecutive primes, p < q, such that both p*q+p-q and p*q-p+q are prime numbers.at n=28A154553
• Depression-type primes with five digits; from left to right digits decrease to and increase from the central digit.at n=6A157083
• Cyclops Sophie-Germain primes.at n=9A183058
• Number of 0..n arrays x(0..8) of 9 elements with zero 6th differences.at n=17A200276
• a(n) is a prime number that cannot be the center term of a length 3 arithmetic progression prime group with a common difference whose number of runs in binary expansion is 2.at n=27A231387
• Fifth prime p such that (p+n)^2+n is prime but (p+j)^2+j is not prime for all 0<j<n.at n=23A238677
• Smallest primes of 4 X 4 semimagic squares formed from consecutive primes.at n=35A270865
• a(n) is the number of partitions of 72*n + 42 into 10 odd squares.at n=41A323891
• Primes p such that (q*s-p*r)/2 and |p*s-q*r|/2 are both prime, where p,q,r,s are consecutive primes.at n=25A341802
• Number of partitions p of n such that (1/4)*max(p) is a part of p.at n=48A363067
• Prime numbersat n=2371