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A248661
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Initial members of prime quadruples (n, n+2, n+54, n+56).
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1
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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
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OFFSET
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1,1
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COMMENTS
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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)).
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LINKS
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EXAMPLE
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For n=17, the numbers 17, 19, 71, 73, are primes.
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PROG
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(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=', ')
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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