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A250109
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Sequence arising from study of multiplicative complexity of symmetric functions over a field with characteristic p.
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1
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-8, 0, -20, -20, -64, -48, -120, -120, -232, -208, -364, -364, -576, -544, -816, -816, -1160, -1120, -1540, -1540, -2048, -2000, -2600, -2600, -3304, -3248, -4060, -4060, -4992, -4928, -5984, -5984, -7176, -7104, -8436, -8436, -9920, -9840, -11480, -11480
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OFFSET
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1,1
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COMMENTS
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No recurrence is known.
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LINKS
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FORMULA
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Empirically for 5000 terms:
Let k = n mod 4.
Formula:
k = 0: a(n) = -n*(n+1)*(n+2)/6.
k = 1: a(n) = -(n+3)*(n^2 + 3*n + 8)/6.
k = 2: a(n) = -(n-2)*(n+2)*(n+3)/6.
k = 3: a(n) = -(n+1)*(n+2)*(n+3)/6.
Recursion:
a(1..12) = (-8, 0, -20, -20, -64, -48, -120, -120, -232, -208, -364, -364).
a(n) = 3*a(n-4) - 3*a(n-8) + a(n-12) - 64, n > 12. (End)
Empirical g.f.: -4*x*(2 -2*x +3*x^2 +2*x^3 +2*x^4 +x^6) / ((1 -x)^4*(1 +x)^3*(1 +x^2)^2). - Colin Barker, Dec 04 2016
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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