83233

Properties

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 33.at n=8A031621
• a(n) = n^4 - n^2 + 1.at n=17A060886
• Primes of the form sigma_4(k)/sigma_2(k), arising in A066109.at n=5A066110
• Primes of the form n^2*totient(n)+1 (or A053191(n) + 1).at n=16A076669
• Class 7+ primes.at n=18A081635
• a(n) = sigma_4(n^2)/sigma_2(n^2).at n=16A084218
• Primes of the form 8*k^2 + 1.at n=13A090685
• Primes of the form 2*n^2+1.at n=31A090698
• Larger of two consecutive primes whose sum is a square.at n=25A118591
• Larger member of twin prime pairs whose sum is a square.at n=12A118593
• Twin prime pairs that sum to a power.at n=29A119768
• Smallest prime divisor of n^4-n^2+1.at n=15A125258
• Primes dividing terms of A128358.at n=2A134360
• a(n) = 72*n^2 + 1.at n=34A158740
• 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=37A162652
• Primes of the form ((p-1)/2)^2+((p+1)/2), where p is prime.at n=38A163418
• Noncomposite numbers in the southwestern ray of the Ulam spiral as oriented on the March 1964 cover of Scientific American.at n=33A168026
• Twin prime pairs which sum to perfect squares.at n=25A232878
• Greatest prime factor of n^6+1.at n=16A240549
• Primes in A258774.at n=33A258776