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%I #9 Jul 20 2024 17:18:08
%S 10,945,132820373046,49123375811021432878640796802876545882185505
%N Number of matchings in the n-Sierpinski tetrahedron graph.
%H Christian Sievers, <a href="/A292669/b292669.txt">Table of n, a(n) for n = 1..6</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/IndependentEdgeSet.html">Independent Edge Set</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Matching.html">Matching</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SierpinskiTetrahedronGraph.html">Sierpinski Tetrahedron Graph</a>
%o (PARI) a(n)={my(s=[1,0,1,0,3]);for(k=2,n,s=vector(5,i,sum(wx=0,2,sum(wy=0,2,sum(wz=0,2,sum(xy=0,2,sum(xz=0,2,sum(yz=0,2,s[1+(i>1)+(wx%2)+(wy%2)+(wz%2)]*s[1+(i>2)+(wx\2)+(xy%2)+(xz%2)]*s[1+(i>3)+(wy\2)+(xy\2)+(yz%2)]*s[1+(i>4)+(wz\2)+(xz\2)+(yz\2)]))))))));[1,4,6,4,1]*s~} \\ _Christian Sievers_, Jul 20 2024
%K nonn
%O 1,1
%A _Eric W. Weisstein_, Sep 20 2017
%E a(4) and beyond from _Christian Sievers_, Jul 20 2024