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A248661
Initial members of prime quadruples (n, n+2, n+54, n+56).
1
5, 17, 137, 227, 827, 1427, 1667, 1877, 2027, 2087, 2657, 3527, 3767, 4217, 4967, 10037, 11117, 11777, 12107, 13877, 17987, 19697, 20717, 21557, 22037, 23687, 24977, 27527, 27737, 34157, 37307, 41177, 42017, 42407, 47657, 48677
OFFSET
1,1
COMMENTS
This sequence is prime n, where there exist two twin prime pairs of (n,n+2), (n+54,n+56).
Excluding 5, this is a subsequence of each of the following: A128468 (a(n)=30*n+17), A039949 (primes, 30n-13), A181605 (twin primes, end 7), and A092340 (prime n, where n^2+2*n divides (fibonacci(n^2)+fibonacci(2*n))).
LINKS
Eric Weisstein's World of Mathematics, Prime Quadruplet.
Eric Weisstein's World of Mathematics, Twin Primes
Wikipedia, Twin prime
EXAMPLE
For n=17, the numbers 17, 19, 71, 73, are primes.
PROG
(Python)
from sympy import isprime
for n in range(1, 10000001, 2):
if isprime(n) and isprime(n+2) and isprime(n+54) and isprime(n+56): print(n, end=', ')
CROSSREFS
Cf. A077800 (twin primes), A128468, A039949, A181605, A092340.
Sequence in context: A096310 A236530 A249520 * A176133 A071057 A181922
KEYWORD
nonn
AUTHOR
Karl V. Keller, Jr., Jan 11 2015
STATUS
approved