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A270754
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Numbers n such that n - 31, n - 1, n + 1 and n + 31 are consecutive primes.
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1
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90438, 258918, 293862, 385740, 426162, 532950, 1073952, 1317192, 1318410, 1401318, 1565382, 1894338, 1986168, 2174772, 2612790, 2764788, 3390900, 3450048, 3618960, 3797250, 3961722, 3973062, 4074870, 4306230, 4648068, 4917360, 5351010, 5460492
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OFFSET
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1,1
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COMMENTS
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This sequence is a subsequence of A014574 (average of twin prime pairs) and A256753.
The terms ending in 0 are divisible by 30 (cf. A249674).
The terms ending in 2 and 8 are congruent to 12 mod 30 and 18 mod 30 respectively.
The numbers n - 31 and n + 1 belong to A049481 (p and p + 30 are primes) and A124596 (p where p + 30 is the next prime).
The numbers n - 31 and n - 1 belong to A049489 (p and p + 32 are primes).
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LINKS
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EXAMPLE
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90438 is the average of the four consecutive primes 90407, 90437, 90439, 90469.
258918 is the average of the four consecutive primes 258887, 258917, 258919, 258949.
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PROG
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(Python)
from sympy import isprime, prevprime, nextprime
for i in range(0, 1000001, 6):
.. if isprime(i-1) and isprime(i+1) and prevprime(i-1) == i-31 and nextprime(i+1) == i+31 : print (i, 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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