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A046023
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Number of ways to color edges of a tetrahedron using <= n colors.
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8
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0, 1, 12, 87, 416, 1475, 4236, 10437, 22912, 45981, 85900, 151371, 254112, 409487, 637196, 962025, 1414656, 2032537, 2860812, 3953311, 5373600, 7196091, 9507212, 12406637, 16008576, 20443125, 25857676, 32418387, 40311712
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n) = (n^6+3*n^4+8*n^2)/12.
G.f.: x*(1+x)*(1+4*x+20*x^2+4*x^3+x^4)/(1-x)^7. - Colin Barker, Jan 30 2012
E.g.f.: exp(x)*x*(12 + 60*x + 108*x^2 + 68*x^3 + 15*x^4 + x^5)/12. - Stefano Spezia, Feb 29 2024
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MAPLE
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A046023 := n->(n^6+3*n^4+8*n^2)/12;
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MATHEMATICA
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LinearRecurrence[{7, -21, 35, -35, 21, -7, 1}, {0, 1, 12, 87, 416, 1475, 4236}, 30] (* Vincenzo Librandi, Jan 31 2012 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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