1,1

Carlos Rivera, The Prime Puzzles & Problems connection.

a(6)=6787314293760 because {2,3,5,7,11,13}={prime(1),prime(2),..., prime(6)} is the set of prime factors of 6787314293760,

all six numbers 2*6787314293760-1,3*6787314293760-1, 5*6787314293760-1,7*6787314293760-1,11*6787314293760-1 & 13*6787314293760-1 are prime and 6787314293760 is the first number with such properties.

Cf. A092023, A092024.

Adjacent sequences: A112720 A112721 A112722 this_sequence A112724 A112725 A112726

Sequence in context: A001684 A076926 A092023 this_sequence A074777 A007280 A102927

hard,nonn

Farideh Firoozbakht (f.firoozbakht(AT)math.ui.ac.ir), Nov 05 2005