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A297532
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Number of maximum matchings in the n-Sierpinski sieve graph.
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1
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3, 2, 144, 8192, 69269232549888, 2658455991569831745807614120560689152, 20629598047085351073781197562197536448467995509610681744292843893938924076606720567385132001811808287432516829184
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OFFSET
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1,1
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LINKS
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Eric Weisstein's World of Mathematics, Matching
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PROG
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(PARI) rd(p)=if(p, pollead(p)*x^poldegree(p), 0);
a(n)={my(s=[1, 0, x, 0]); for(k=2, n, s=vector(4, i, sum(xy=0, 2, sum(xz=0, 2, sum(yz=0, 2, rd(s[1+(i>1)+(xy%2)+(xz%2)]*s[1+(i>2)+(xy\2)+(yz%2)]*s[1+(i>3)+(xz\2)+(yz\2)])))))); pollead([1, 3, 3, 1]*s~)} \\ Christian Sievers, Jul 21 2024
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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