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A203197 (n-1)-st elementary symmetric function of the first n terms of (1,3,9,27,...)=A000244. 1
1, 4, 39, 1080, 88209, 21493836, 15683355351, 34309958505840, 225130514549271201, 4431394012508602048404, 261672339357326993189906439, 46354644349343413982791427120040, 24634789450813795903041020740742981169 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..13.

FORMULA

a(n) = (1/2)*(3-1/3^(n-1))*3^(binomial(n,2)). - Emanuele Munarini, Sep 14 2017

MATHEMATICA

f[k_] := 3^(k - 1); t[n_] := Table[f[k], {k, 1, n}]

a[n_] := SymmetricPolynomial[n - 1, t[n]]

Table[a[n], {n, 1, 16}]  (* A203197 *)

Table[1/2 (3 - 1/3^(n-1)) 3^Binomial[n, 2], {n, 1, 20}] (* Emanuele Munarini, Sep 14 2017 *)

CROSSREFS

Cf. A000244, A003462 (1st symm. func.), A203243 (2nd symm. func.).

Sequence in context: A165434 A341473 A086217 * A094156 A266859 A049475

Adjacent sequences:  A203194 A203195 A203196 * A203198 A203199 A203200

KEYWORD

nonn

AUTHOR

Clark Kimberling, Dec 30 2011

STATUS

approved

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Last modified June 20 20:22 EDT 2021. Contains 345233 sequences. (Running on oeis4.)