22481

Properties

Appears in sequences

• Denominators of continued fraction convergents to sqrt(975).at n=6A042887
• Primes p for which the period of reciprocal = (p-1)/8.at n=35A056213
• Primes p such that 2^p-1 and the p-th Fibonacci number have a common factor. Prime terms of A074776.at n=9A080050
• Smallest member of a pair of consecutive twin prime pairs that have three primes between them.at n=31A089635
• Numbers k such that sigma(phi(k))-phi(sigma(k)) is nonzero and is divisible by (k+1), that is A065395(k)/(k+1) = (phi(sigma(k))-sigma(phi(k)))/(k+1) is a nonzero integer.at n=14A092586
• Numbers k such that sigma(phi(k)) - phi(sigma(k)) is nonzero and divisible by sigma(k), that is A065395(k)/A000203(k) is a nonzero integer.at n=23A092588
• Lesser of twin balanced primes (A090403).at n=11A096694
• Primes p such that p + 2, 18*p^2 + 1, and 18*(p+2)^2 + 1 are all primes.at n=10A115272
• Primes such that applying "reverse and add" twice produces two more primes.at n=5A174402
• Lesser of twin primes p1 such that p1*p2+-6 are prime numbers.at n=11A174955
• Lesser of twin primes p1 such that p1*p2-4 and p1*p2-6 are twin prime numbers.at n=16A174957
• Fibonacci-type sequence based on bitwise exclusive-or: a(0) = 0, a(1) = 1 and a(n) = a(n-1) + (a(n-1) xor a(n-2)).at n=15A182201
• Number of partitions of n such that the number of parts and the smallest part are not coprime.at n=52A201025
• Primes of the form 2*k^2 + 9.at n=40A201476
• Primes of the form 8n^2 + 9.at n=21A201705
• a(n) = 25*n^2 + 15*n + 1021.at n=29A214732
• Primes p such that p = q^2 + 8*r^2 where q and r are also primes.at n=26A260556
• Primes of the form abs(103*n^2 - 4707*n + 50383) in order of increasing nonnegative n.at n=7A267252
• Primes 8k + 1 preceding the maximal gaps in A269424.at n=9A269425
• Lesser of twin primes such that sum of twin prime pair is the sum of 2 nonzero squares.at n=41A270245