OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
prime(10)*prime(11)*prime(12) - 1 = 29*31*37 - 1 = 33262= 2*16631, hence 10 is
a term.
MATHEMATICA
PrimePi/@Transpose[Select[Partition[Prime[Range[2000]], 3, 1], PrimeOmega[ Times@@#-1]==2&]][[1]] (* Harvey P. Dale, Mar 15 2015 *)
PROG
(PARI) for(n=1, 1900, if(bigomega(prime(n)*prime(n+1)*prime(n+2)-1)==2, print1(n, ", ")))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Klaus Brockhaus, Mar 29 2005
STATUS
approved