19211

Properties

Appears in sequences

• Smallest prime p==3 (mod 8) such that Q(sqrt(-p)) has class number 2n+1.at n=37A002148
• Primes that remain prime through 3 iterations of function f(x) = 10x + 3.at n=41A023300
• Primes p such that 2^p-1 and the p-th Fibonacci number have a common factor. Prime terms of A074776.at n=7A080050
• Smallest prime of the form prime(k) concatenated with prime(k+n).at n=38A089782
• Primes A005382(n) + A005384(n) - 1 with a twin prime A005382(n) + A005384(n) + 1.at n=27A099109
• Index k of the first occurrence of A019565(2n-1) as the smallest term that makes prime(k)-A019565(2n-1) prime.at n=29A103792
• Primes congruent to 36 mod 59.at n=33A142763
• Primes congruent to 57 mod 61.at n=34A142855
• Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1001-1111-1000 pattern in any orientation.at n=14A146845
• The 4k+3 integers corresponding to the record positions in A165601.at n=39A166046
• Primes remaining primes under map 2<=>9 (interchange of decimal digits 2 and 9).at n=35A198146
• Primes of the form 7k^3+3.at n=2A201184
• Primes of the form 2*k^2 + 3.at n=20A201473
• Primes of the form 8n^2 + 3.at n=11A201611
• Primes of the form 5n^2 - 9.at n=12A201790
• Prime p such that p and p+2 are twin primes and p^2+p-1 p^2+p+1 are also twin primes.at n=10A228968
• Primes of the form T(k) + S(k) + 1 where T(k) is the k-th triangular number and S(k) is the k-th square number.at n=26A229080
• Primes p such that p+2 and q are primes, where q is concatenation of binary representations of p and p+2: q = p * 2^L + p+2, where L is the length of binary representation of p+2: L=A070939(p+2).at n=21A232238
• Primes whose base-7 representation also is the base-4 representation of a prime.at n=49A235617
• Primes p such that p1 = ceiling(p/2) + p is prime and p2 = floor(p1/2) + p is prime.at n=41A242366