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A203238
a(n)=(n-1)-st elementary symmetric function of the first n terms of (2, -4, 6, -8, 10, ...).
1
1, -2, -20, 112, 1504, -14208, -244992, 3274752, 69267456, -1199554560, -30106091520, 640796590080, 18622701895680, -470423898685440, -15541046083584000, 454463600984064000, 16822958391558144000, -559005839520694272000
OFFSET
1,2
MATHEMATICA
f[k_] := (2 k) (-1)^(k + 1)
t[n_] := Table[f[k], {k, 1, n}]
a[n_] := SymmetricPolynomial[n - 1, t[n]]
Table[a[n], {n, 1, 22}] (* A203238 *)
CROSSREFS
Cf. A181174.
Sequence in context: A282818 A001797 A084894 * A061004 A278772 A213432
KEYWORD
sign
AUTHOR
Clark Kimberling, Dec 30 2011
STATUS
approved