%I #18 Jan 09 2016 12:25:45
%S 1,2,2,3,6,56,55525372
%N a(n) is the a(n-1)-th a(n-2)-dimensional simplex number, starting with the terms 1, 2.
%C The next term is too large to include.
%H OEIS Wiki, <a href="http://oeis.org/wiki/Simplicial_polytopic_numbers">Simplicial polytopic numbers</a>
%e 56 is the 6th 3-simplex (or tetrahedral) number = A000292(6).
%e 55525372 is the 56th 6-simplex number = A000579(61).
%e The next term will be the 55525372th 56-simplex number.
%Y Cf. A000217, A000292, A000579.
%K nonn
%O 1,2
%A _Robin Powell_, Nov 09 2015