OFFSET
2,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 2..1000
FORMULA
a(n)=[p(n)*p(n+1)/p(n+2)], where p(n) is the n-th prime and [] is the floor function .
For n > 3, prime(n)/2 < a(n) < prime(n). prime(n) - a(n) << log(n)^2 under Cramer's conjecture. Weaker estimates follow from the Prime Number Theorem. - Charles R Greathouse IV, Jan 26 2012
EXAMPLE
[2*3/5]=1; [3*5/7]=2; [5*7/11]=3
MATHEMATICA
Table[Floor[Prime[n]*Prime[n + 1]/Prime[n + 2]], {n, 1, 50}] (* G. C. Greubel, Jun 28 2017 *)
PROG
(PARI) p=2; q=3; forprime(r=5, 1e3, print1(p*q\r", "); p=q; q=r) \\ Charles R Greathouse IV, Jan 26 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
Tyler Carrico, Jan 26 2012
EXTENSIONS
a(14)-a(15) corrected, a(16)-a(59) from Charles R Greathouse IV, Jan 26 2012
STATUS
approved