19121

Properties

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted then there are a pair of central terms both equal to 10.at n=28A031423
• Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 68 ones.at n=34A031836
• Numbers p from A001125 such that 2*p-3 is prime.at n=26A063939
• Primes p such that the next prime after p can be obtained from p by adding the product of the digits of p.at n=12A089823
• If p(k) is the k-th prime, then the n-th set of 3 consecutive cousin prime pairs starts at p(a(n)).at n=27A095970
• Prime numbers, isolated from neighboring primes by >14.at n=33A137874
• Prime numbers, isolated from neighboring primes by >16.at n=19A137875
• Primes congruent to 28 mod 61.at n=33A142826
• Primes p of the form 4*k+1 for which s=26 is the least positive integer such that s*p-(floor(sqrt(s*p)))^2 is a square.at n=22A145050
• a(n) = 12*n^2 + 22*n + 11.at n=39A154106
• Numbers k such that k^p-p is prime, where p is product of the digits of k.at n=19A178328
• Primes which are the sum of two numbers of the form k*(k+1)^2/2.at n=39A210646
• Primes of form n^2 + 625.at n=28A256777
• Primes of the form prime(n) + n + n^2.at n=43A267421
• Five-digit primes whose first, third, and fifth digits are the same.at n=23A269066
• Primes whose digit reversal is the product of two (not necessarily distinct) emirps.at n=40A345664
• Primes having only {1, 2, 9} as digits.at n=29A385776
• Prime numbersat n=2170