49681

Properties

Appears in sequences

• Smallest prime in class n (sometimes written n+) according to the Erdős-Selfridge classification of primes.at n=7A005113
• Let Dedekind's psi(m) = product of (p+1)p^(e-1) for primes p, where p^e is a factor of m. Iterating psi(m) eventually results in a number of form 2^a*3^b. a(n) is the smallest number that requires n steps to reach such a number.at n=8A019268
• Numbers k such that (3^k - 1)/2 is prime.at n=14A028491
• Class 8+ primes.at n=0A081636
• Primes p such that p*(p-2) divides 2^(p-1)-1.at n=16A081762
• Numbers n such that 3^n has the form 2p-+1 where p is prime.at n=20A096723
• Indices of primes in sequence defined by A(0) = 39, A(n) = 10*A(n-1) - 1 for n > 0.at n=21A101847
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, -1), (-1, 0, 1), (1, 0, 0), (1, 1, -1), (1, 1, 1)}.at n=8A150752
• Primes p such that (p+1)/2, (p+2)/3 and (p+3)/4 are also primes.at n=4A163573
• Primes p of the form |prime(n+2)^2-prime(n+1)^2-prime(n)^2|, (absolute values).at n=22A176134
• a(n) = prime(n)^2 - n.at n=47A182174
• Primes of the form 6*k^2 - 5.at n=27A201791
• Primes of the form prime(k)^2 - k.at n=7A227890
• Numbers n such that (n^n-2)/(n-2) is an integer.at n=40A242787
• Numbers n such that (n-1)^2-1 divides 2^(n-1)-1.at n=17A260406
• a(n) = Sum_{d|n} d^(2*n/d - 1).at n=15A308688
• Numbers k such that -3 is a quadratic residue (not necessarily coprime) modulo k, k + 1, k + 2 and k + 3.at n=28A318527
• Primes containing nonprime digits (from 1 to 9) in their decimal expansion and whose digits are distinct, i.e., consisting of only digits 1, 4, 6, 8, 9.at n=26A323391
• Odd integers k such that 2^((k-1)/2) == 1 (mod k*(k-2)).at n=9A337846
• Numbers k such that tau(k) + tau(k+1) + tau(k+2) + tau(k+3) = 16, where tau is the number of divisors function A000005.at n=29A350686