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A092024
a(n) is the smallest number m such that m has n distinct prime divisors and if p is a prime divisor of m then p*m +1 is prime.
3
2, 6, 354, 210, 43860, 463980, 189583590, 6958972020, 200007607800, 60958204112190, 3337686588286050
OFFSET
1,1
LINKS
Carlos Rivera, Puzzle 334. Farideh & the 2004 year, The Prime Puzzles & Problems connection.
EXAMPLE
a(7)=189583590 because 189583590=2*3*5*7*41*97*227, all the seven numbers 2*189583590+1, 3*189583590+1, 5*189583590+1, 7*189583590+1, 41*189583590+1, 97*189583590+1 and 227*189583590+1 are prime numbers and 189583590 is the smallest number m with such property.
CROSSREFS
Cf. A092023.
Sequence in context: A264410 A135014 A321571 * A252741 A069261 A053608
KEYWORD
more,nonn
AUTHOR
Farideh Firoozbakht, Feb 19 2004
EXTENSIONS
a(10) from Michael S. Branicky, Feb 27 2023
a(11) from Michael S. Branicky, Mar 08 2023
STATUS
approved