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A120851
Numbers n such that n is prime and is equal to the product of the first k primes minus the sum of the first k primes, for some k.
1
193, 29989, 13082761331669749
OFFSET
1,1
COMMENTS
It is in the spirit of A096345 (only for 2 consecutive primes).
The corresponding values of k are 4, 6, 14, 548, 1190, ... a(4) = 2.452... * 10^1691, a(5) = 1.263... x 10^4142. - Amiram Eldar, Dec 19 2018
EXAMPLE
193 = -(2+3+5+7)+(2*3*5*7) and 193 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
KEYWORD
nonn,bref
AUTHOR
Carlos Alves, Jul 08 2006
EXTENSIONS
The next term is too large to include.
STATUS
approved