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A057706 Smaller of twin primes whose average is a primorial number. 4
5, 29, 2309 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

According to Caldwell, the next term, if it exists, has more than 100000 digits. - T. D. Noe, May 08 2012

LINKS

Table of n, a(n) for n=1..3.

Chris K. Caldwell, Primorial prime

EXAMPLE

(5+7)/2 = 6 = 2*3, (29+31)/2 = 30 = 2*3*5, (2309+2311)/2 = 2310 = 2*3*5*7*11.

MATHEMATICA

Select[FoldList[Times, Prime@ Range@ 40], AllTrue[# + {-1, 1}, PrimeQ] &] - 1 (* Michael De Vlieger, Jul 15 2017 *)

CROSSREFS

Cf. A014545, A005234, A057704, A006794, A002110.

Sequence in context: A057208 A046842 A175905 * A057705 A237188 A086720

Adjacent sequences:  A057703 A057704 A057705 * A057707 A057708 A057709

KEYWORD

nonn,bref

AUTHOR

Labos Elemer, Oct 24 2000

EXTENSIONS

Offset corrected by Arkadiusz Wesolowski, May 08 2012

STATUS

approved

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Last modified January 28 03:49 EST 2020. Contains 331317 sequences. (Running on oeis4.)