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A094710
Smaller of a pair (p,q) of primes with (p+q)/2=prime(n)# and q-p is minimal.
2
5, 29, 197, 2309, 30013, 510451, 9699667, 223092791, 6469693129, 200560490047, 7420738134571, 304250263527139, 13082761331669881, 614889782588491043, 32589158477190044657, 1922760350154212638159, 117288381359406970982957, 7858321551080267055878717, 557940830126698960967414867
OFFSET
2,1
COMMENTS
a(n) = Max{p prime: (p+q)/2=prime(n)# for another prime q>p};
a(n) = A002110(n) - A094709(n); (a(n) + A094711(n))/2 = A002110(n).
PROG
(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(20)) # Michael S. Branicky, May 29 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, May 21 2004
EXTENSIONS
Corrected by T. D. Noe, Nov 15 2006
a(12)-a(20) from Donovan Johnson, Apr 27 2008
STATUS
approved