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A120850 Numbers n such that n is prime and is equal to the sum of the first k primes plus the product of the first k primes, for some k. 1
11, 227, 30071, 24647906487115793512432470614609487044327490547070674282967249490409801198254927547005559122946385681862066942903289, 62797802135946735863734268232365323600796854989079318289826397214991489160762431714712874321823048719463864215556568570809157897364620234601356930764612312239892910549558645813243759770009793795858849126389709 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

It is in the spirit of A096342 (only for 2 consecutive primes) and of A013918 (all primes but only the sum).

The corresponding values of k are 2, 4, 6, 60, 96, ... - Amiram Eldar, Dec 19 2018

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

11=(2+3)+(2*3) and 11 is prime.

227= (2+3+5+7)+(2*3*5*7) and 227 is prime.

MATHEMATICA

tb = {}; Do[pq = Plus @@ Prime[Range[1, k]] + Times @@ Prime[Range[1, k]]; If[PrimeQ[pq], AppendTo[tb, pq]], {k, 1, 200}]; tb

CROSSREFS

Cf. A096342, A013918, A120851.

Sequence in context: A187646 A170948 A245076 * A289716 A305141 A296592

Adjacent sequences:  A120847 A120848 A120849 * A120851 A120852 A120853

KEYWORD

nonn

AUTHOR

Carlos Alves, Jul 08 2006

STATUS

approved

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Last modified August 25 10:10 EDT 2019. Contains 326324 sequences. (Running on oeis4.)