%I #11 Sep 08 2014 15:14:39
%S 6,24,1104,13957632,859428866274361344,
%T 1736323895937560083755071573748292907445157625856
%N Numbers of directed Hamiltonian paths in the n-Sierpinski sieve graph.
%C Explicit formula and asymptotic are given by Chang and Chen (2011).
%C a(7) contains 137 decimal digits.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HamiltonianPath.html">Hamiltonian Path</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SierpinskiSieveGraph.html">Sierpinski Sieve Graph</a>
%H S.-C. Chang, L.-C. Chen. Hamiltonian walks on the Sierpinski gasket, J. Math. Phys. 52 (2011), 023301. doi:<a href="http://dx.doi.org/10.1063/1.3545358">10.1063/1.3545358</a>. arXiv:<a href="http://arxiv.org/abs/0909.5541">0909.5541</a>
%F a(n) = A246957(n)*2.
%Y Cf. A246957, A246958, A246959
%K nonn
%O 1,1
%A _Eric W. Weisstein_, Dec 28 2013
%E a(5)-a(6) added by _Max Alekseyev_, Sep 08 2014