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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 (list; graph; refs; listen; history; text; internal format)
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).

LINKS

Table of n, a(n) for n=2..20.

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

Cf. A002110, A094709, A094711.

Sequence in context: A201856 A201115 A199419 * A216313 A108453 A201203

Adjacent sequences:  A094707 A094708 A094709 * A094711 A094712 A094713

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

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Last modified May 19 08:11 EDT 2022. Contains 353826 sequences. (Running on oeis4.)