%I #9 Mar 31 2012 13:22:09
%S 1,2,2,6,10,15,17,22,30,42,100,77,96,103,120,94,141,206,339,548,843,
%T 1409,978,1198,1920,2837,5377
%N The largest k corresponding to n=A181542(.) such that 3^n-3^k-1 and 3^n-3^k+1 are twin primes.
%Y Cf. A181515, A181523, A181542
%K nonn
%O 1,2
%A _Pierre CAMI_, Jan 29 2011