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A096195
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a(n) = number of distinct solutions to the set of equations 1 +- x +- x^2 +- ... +- x^n = 0 over the complex numbers.
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1
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2, 8, 16, 64, 106, 324, 696, 1856, 4046, 10240, 19084, 49152, 98110, 218140, 464084, 1047744, 2123446, 4718592, 9632740, 20666444
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..20.
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EXAMPLE
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a(2) = 8 because the set of equations 1 +- x +- x^2 = 0 generates 8 distinct solutions.
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MATHEMATICA
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a[n_] := a[n] = Length[Union[ Flatten[x /. Table[Solve[1 + Sum[(-1)^IntegerDigits[k, 2, n + 1][[p + 1]]x^p, {p, n}] == 0], {k, 0, 2^n - 1}]]]]; Table[a[n], {n, 10}]
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CROSSREFS
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Cf. A036289 (total number of solutions to the equations).
Sequence in context: A100243 A026523 A066792 * A094014 A098232 A354275
Adjacent sequences: A096192 A096193 A096194 * A096196 A096197 A096198
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KEYWORD
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more,nonn
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AUTHOR
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Josh Locker (jlocker(AT)mail.rochester.edu), Jul 26 2004
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EXTENSIONS
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More terms from Robert G. Wilson v and Labos Elemer, Jul 27 2004
a(17)-a(19) from Robert G. Wilson v, May 05 2013
a(20) from Robert G. Wilson v, May 05 2013
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STATUS
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approved
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