OFFSET
1,2
COMMENTS
LINKS
FORMULA
For n > 1, a(n) = p*q, where p, q are primes, p+q = A002110(n) and q >= p and q - p is minimal. - David A. Corneth, Jan 17 2024 [This depends on Goldbach's conjecture being valid, at least on primorials, for which there is strong empirical evidence though.] - Antti Karttunen, Jan 19 2024
EXAMPLE
PROG
(PARI) a(n) = {if(n==1, return(0)); pr = vecprod(primes(n)); prover2 = pr/2; forprime(p = prover2, oo, if(isprime(pr - p), return(p*(pr-p))))} \\ David A. Corneth, Jan 17 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 16 2024
EXTENSIONS
More terms from David A. Corneth, Jan 17 2024
STATUS
approved