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 A242327 Primes p for which (p^n) + 2 is prime for n = 1, 3, 5, and 7. 2
 132749, 1175411, 3940799, 5278571, 11047709, 12390251, 15118769, 21967241, 22234871, 26568929, 31809959, 32229341, 32969591, 35760551, 38704661, 43124831, 43991081, 49248971, 50227211, 51140861, 53221631, 55568171, 59446109, 63671651, 71109161, 76675589 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subsequence of A001359 and A048637. LINKS Abhiram R Devesh, Table of n, a(n) for n = 1..50 EXAMPLE p = 132749 (prime); p + 2 = 132751 (prime); p^3 + 2 = 2339342304585751 (prime); p^5 + 2 = 41224584878413873150038751 (prime); p^7 + 2 = 726471878470342746448722269536491751 (prime). PROG (Python) import sympy from sympy.ntheory import isprime, nextprime n=2 while True:     n1=n+2     n2=n**3+2     n3=n**5+2     n4=n**7+2     ##.Check if n1, n2, n3 and n4 are also primes     if all(isprime(x) for x in [n1, n2, n3, n4]):         print(n, ", ", n1, ", ", n2, ", ", n3, ", ", n4)     n=nextprime(n) (PARI) isok(p) = isprime(p) && isprime(p+2) && isprime(p^3+2) && isprime(p^5+2) && isprime(p^7+2); \\ Michel Marcus, May 15 2014 (Sage) def is_A242327(n):     return is_prime(n) and all([is_prime(n^(2*k+1)+2) for k in range(4)]) filter(is_A242327, range(3940800)) # Peter Luschny, May 15 2014 CROSSREFS Cf. A001359, A006512, A048637. Sequence in context: A161356 A236735 A238233 * A319063 A015407 A204536 Adjacent sequences:  A242324 A242325 A242326 * A242328 A242329 A242330 KEYWORD nonn AUTHOR Abhiram R Devesh, May 10 2014 STATUS approved

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Last modified September 27 00:14 EDT 2020. Contains 337378 sequences. (Running on oeis4.)