OFFSET
1,1
EXAMPLE
Fourth row is 5, 11, 23, 47, so a(4) = 86.
PROG
(Magma) f:=function(n) m:=1; while not IsPrime(m*n+1) do m+:=1; end while; return m*n+1; end function; [ &+[ k eq 1 select f(j) else f(Self(k-1)): k in [1..j] ]: j in [1..17] ];
CROSSREFS
KEYWORD
nonn
AUTHOR
Klaus Brockhaus, May 30 2009
STATUS
approved