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A272816
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Prime pairs of the form (p, p+20).
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3
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3, 23, 11, 31, 17, 37, 23, 43, 41, 61, 47, 67, 53, 73, 59, 79, 83, 103, 89, 109, 107, 127, 131, 151, 137, 157, 173, 193, 179, 199, 191, 211, 251, 271, 257, 277, 263, 283, 293, 313, 311, 331, 317, 337, 347, 367, 353, 373, 359, 379, 389, 409, 401, 421
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OFFSET
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1,1
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COMMENTS
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p and p+20 are not necessarily consecutive primes: (887, 907) is the first pair of consecutive primes that belongs to the sequence.
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LINKS
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FORMULA
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EXAMPLE
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The prime pairs are (3, 23), (11, 31), (17, 37) etc.
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MATHEMATICA
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Flatten[{#, # + 20}&/@Select[Prime[Range[200]], PrimeQ[# + 20] &]]
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PROG
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(Magma) &cat [[p, p+20]: p in PrimesUpTo(1000) | IsPrime(p+20)];
(Python)
from gmpy2 import is_prime
for n in range(1000):
if(is_prime(n) and is_prime(n+20)):
print('{}, {}'.format(n, n+20), end=', ')
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CROSSREFS
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Cf. similar sequences listed in A272815.
Prime pairs of the form (p, p+k): A077800 (k=2), A094343 (k=4), A156274 (k=6), A156320 (k=8), A140445 (k=10), A156323 (k=12), A140446 (k=14), A272815 (k=16), A156328 (k=18), this sequence (k=20), A140447 (k=22).
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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