OFFSET
1,1
EXAMPLE
Prime numbers are 2,3,5,7,11,13,17,... 2nd prime is 3, 3rd prime is 5 and the 5th prime is 11, so we get 2*3=6, 3*5=15, 5*11=55...
MATHEMATICA
#*Prime[#]&/@Prime[Range[40]] (* Harvey P. Dale, Jun 24 2018 *)
PROG
(PARI) a(n) = prime(n) * prime(prime(n)) \\ Michel Marcus, Jun 26 2013
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Y. Kelly Itakura (yitkr(AT)mta.ca), Aug 22 2002
STATUS
approved