19183

Properties

Appears in sequences

• Primes of form k^2 + k + 1.at n=39A002383
• Primes of the form p^k - p + 1 for prime p.at n=16A034915
• Primes of the form p^2 - p + 1 where p is prime.at n=6A074268
• First prime after phi(prime(n)^2).at n=33A079477
• Number of ordered quadruples (a,b,c,d) with gcd(a,b,c,d)=1 (1 <= {a,b,c,d} <= n).at n=11A082540
• Primes of the form 1 + n + n^2 + n^3 + ... + n^k, n > 1, k > 1.at n=41A085104
• Primes of the form p^k - p^(k-1) + 1 for some prime p and integer k > 1.at n=16A087126
• Primes p such that q-p = 24, where q is the next prime after p.at n=32A098974
• Numerators of the convergents in the continued fraction expansion for the constant given by A100338, where the partial quotients equal A006519 (greatest power of 2 dividing n).at n=12A100340
• p^2-p+1 central polygonal numbers with prime indices A002061(prime(n)).at n=33A119959
• Let f(k) = exp(Pi*sqrt(k)); sequence gives numbers k such that ceiling(f(k)) - f(k) < 1/10^3.at n=30A127022
• Let f(n) = exp(Pi*sqrt(n)); sequence gives numbers n such that ceiling(f(n)) - f(n) < 1/10^4.at n=10A127023
• Primes of the form p^e - p^(e-1) + p^(e-2) - ... + (-1)^e, where p is prime.at n=15A127727
• Primes congruent to 50 mod 53.at n=38A142580
• Primes congruent to 8 mod 59.at n=36A142735
• Primes p such that there are positive integers m and n and a prime q such that p = m^2+m-q = n^2+n+q.at n=23A162652
• Primes of the form ((p-1)/2)^2+((p+1)/2), where p is prime.at n=24A163418
• Noncomposite numbers in the southwestern ray of the Ulam spiral as oriented on the March 1964 cover of Scientific American.at n=17A168026
• Primes of the form n^2 + n + 1 where n is nonprime.at n=29A185632
• 50k^2-40k-17 interleaved with 50k^2+10k+13 for k=>0.at n=40A217893