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A127850
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a(n)=(2^n-1)*2^(n(n-1)/2)/(2^(n-1)).
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3
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0, 1, 3, 14, 120, 1984, 64512, 4161536, 534773760, 137170518016, 70300024700928, 72022409665839104, 147537923792657448960, 604389122831019749146624, 4951457925686617442302820352
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OFFSET
| 0,3
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COMMENTS
| To base 2, this is given by A127851.
From Clark Kimberling, Dec 29 2011 (start):
a(n)=(n-1)-st elementary symmetric function of {1,2,4,6,16,...,2^(n-1)}; see Mathematica program.
(end)
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FORMULA
| a(n)=2^C(n,2)*(2^n-1)/2^(n-1)
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MATHEMATICA
| f[k_] := 2^(k - 1); t[n_] := Table[f[k], {k, 1, n}]
a[n_] := SymmetricPolynomial[n - 1, t[n]]
Table[a[n], {n, 1, 16}] (* A127850 *)
(* Clark Kimberling, Dec 29 2011 *)
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CROSSREFS
| Cf. A122743, A203011.
Sequence in context: A007140 A122081 A161936 * A186772 A061029 A096657
Adjacent sequences: A127847 A127848 A127849 * A127851 A127852 A127853
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KEYWORD
| easy,nonn
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Feb 02 2007
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