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A006718
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Number of golygons of length 8n.
(Formerly M3707)
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3
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1, 4, 112, 8432, 909288, 121106960, 18167084064, 2956370702688, 510696155882492, 92343039606440064, 17311893232788414400, 3342127071364266721200, 661066887819006986788620, 133456726466163517072371360
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OFFSET
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0,2
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COMMENTS
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A007219 is the main entry for golygons.
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REFERENCES
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N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
I. Vardi, Computational Recreations in Mathematica. Addison-Wesley, Redwood City, CA, 1991, p. 92.
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LINKS
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Eric Weisstein's World of Mathematics, Golygon
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FORMULA
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MATHEMATICA
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p1[n_] := Product[x^k + 1, {k, 1, n - 1, 2}] // Expand; p2[n_] := Product[x^k + 1, {k, 1, n/2}] // Expand; c[n_] := Coefficient[p1[n], x, n^2/8] * Coefficient[p2[n], x, n (n/2 + 1)/8]; a[n_] := c[8*n]; Table[a[n], {n, 0, 11}] (* Jean-François Alcover, Jul 24 2013, after Eric W. Weisstein *)
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CROSSREFS
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See A007219 for much more information about golygons.
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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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