%I #3 Mar 30 2012 18:40:29
%S 0,0,1,2,24,3136,53798080,15832480722303616,
%T 745527911414639917440582097294401,
%U 1653079675982713719400420113305863285438472194540328413077493166464
%N Tribonacci(heptanacci(n)).
%F a(n) = A000073(A066178(n)).
%e Heptanacci(10) = A066178(10) = 504, so tribonacci(heptanacci(10)) =
%e A000073(504) ~ 4.4 * 10^133.
%Y Cf. A000073, A066178, A007570.
%K easy,nonn
%O 0,4
%A _Jonathan Vos Post_, Nov 13 2005