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A094711
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Larger of a pair (p,q) of primes with (p+q)/2=prime(n)# and q-p is minimal.
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2
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7, 31, 223, 2311, 30047, 510569, 9699713, 223092949, 6469693331, 200560490213, 7420738135049, 304250263527281, 13082761331670179, 614889782588491777, 32589158477190044803, 1922760350154212639981, 117288381359406970983583
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OFFSET
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2,1
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COMMENTS
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a(n) = Min{p prime: (p+q)/2=prime(n)# for another prime q<p};
a(n) = A002110(n) + A094709(n); (a(n) + A094710(n))/2 = A002110(n).
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LINKS
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Table of n, a(n) for n=2..18.
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PROG
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(Python)
from sympy import isprime, prime, primerange
def aupton(terms):
phash, alst = 2, []
for p in primerange(3, prime(terms)+1):
phash *= p
for k in range(1, phash//2):
if isprime(phash-k) and isprime(phash+k): alst.append(phash+k); break
return alst
print(aupton(18)) # Michael S. Branicky, May 29 2021
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CROSSREFS
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Cf. A002110, A094709, A094710.
Sequence in context: A060015 A261558 A241456 * A333735 A221875 A143564
Adjacent sequences: A094708 A094709 A094710 * A094712 A094713 A094714
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KEYWORD
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nonn
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AUTHOR
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Reinhard Zumkeller, May 21 2004
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EXTENSIONS
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Corrected by T. D. Noe, Nov 15 2006
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 01 2008
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STATUS
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approved
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