57527

Properties

Appears in sequences

• Primes p such that x^49 = 2 has no solution mod p, but x^7 = 2 has a solution mod p.at n=19A059667
• Primes p that have exactly three primitive roots that are not primitive roots mod p^2.at n=26A060519
• Let t = coefficient of x^(2n+1) in expansion of sin(x)/(1-x^2); a(n)=denominator(t)-numerator(t).at n=4A067621
• Twin primes whose digits are primes.at n=15A087367
• Primes p such that p and p+2 are twin primes and also the strings 987654321p and 987654321p+2 are twin primes.at n=19A103818
• Primes p such that p + 2, 18*p^2 + 1, and 18*(p+2)^2 + 1 are all primes.at n=18A115272
• Primes p such that |100-p|, |1000-p|, |10000-p| and |100000-p| are also primes.at n=36A126021
• Triangle read by rows: T(n,k) is the number of permutations of {1,2,...,n} having k up-down cycles (0<=k<=n). A cycle (b(1), b(2), ...) is said to be up-down if, when written with its smallest element in the first position, it satisfies b(1)<b(2)>b(3)<... .at n=45A186358
• Number of permutations of {1,2,...,n} having no up-down cycles. A cycle (b(1), b(2), ...) is said to be up-down if, when written with its smallest element in the first position, it satisfies b(1)<b(2)>b(3)<... .at n=9A186359
• a(n) = ((2*n+2)*(2*n+3) - 1)*a(n-1) + 2*n*(2*n+1)*a(n-2), a(0)=1, a(1)=19.at n=3A206308
• Primes that contain only the digits (2, 5, 7).at n=26A214705
• Primes p for which exactly five bases b with 1 < b < p exist such that p is a base b Wieferich prime.at n=17A255208
• Primes p such that p+2, 3*p+2 and 3*p+8 are also primes.at n=26A278138
• Primes equal to a pentagonal number plus 1.at n=36A285789
• Sum of the third largest parts in the partitions of n into 8 parts.at n=47A308996
• Prime numbersat n=5829