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A105093 Numbers n such that n = prime(k) + prime(k+3) = prime(k+1) + prime(k+2) for some k. 3
18, 24, 30, 36, 60, 84, 120, 162, 204, 210, 216, 240, 288, 330, 372, 390, 456, 520, 540, 624, 726, 762, 798, 840, 852, 882, 924, 978, 990, 1104, 1140, 1164, 1200, 1392, 1410, 1428, 1530, 1632, 1650, 1716, 1740, 1764, 1794, 1848, 1974, 2052, 2100, 2112, 2184 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Goldbach Conjecture

EXAMPLE

a(1)=18 because prime(3)+prime(6)=prime(4)+prime(5)=5+13=7+11=18.

MATHEMATICA

lst = {}; Do[ If[ Prime[n] + Prime[n + 3] == Prime[n + 1] + Prime[n + 2], AppendTo[lst, Prime[n] + Prime[n + 3]]], {n, 184}]; lst (* Robert G. Wilson v, Apr 07 2005 *)

PROG

(Python)

from sympy import nextprime

A105093_list, plist = [], [2, 3, 5, 7]

while len(A105093_list) < 10000:

    m = plist[0]+plist[3]

    if m == plist[1]+plist[2]:

        A105093_list.append(m)

    plist = plist[1:] + [nextprime(plist[-1])] # Chai Wah Wu, Mar 30 2020

CROSSREFS

Cf. A001172, A000954, first primes in A022885.

Sequence in context: A160810 A076771 A179014 * A334015 A162331 A092536

Adjacent sequences:  A105090 A105091 A105092 * A105094 A105095 A105096

KEYWORD

nonn

AUTHOR

Giovanni Teofilatto, Apr 06 2005

EXTENSIONS

Edited and extended by Robert G. Wilson v, Apr 07 2005

STATUS

approved

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Last modified November 26 21:07 EST 2021. Contains 349344 sequences. (Running on oeis4.)