Re: Sum of Products

*To*: mathgroup at smc.vnet.net*Subject*: [mg126674] Re: Sum of Products*From*: Bob Hanlon <hanlonr357 at gmail.com>*Date*: Wed, 30 May 2012 04:11:26 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <201205290948.FAA06747@smc.vnet.net>

SymmetricPolynomial, for example, SymmetricPolynomial[2, {a, b, c}] == Total[Times @@@ Subsets[{a, b, c}, {2}]] // Simplify True SymmetricPolynomial[2, {a, b, c, d}] == Total[Times @@@ Subsets[{a, b, c, d}, {2}]] // Simplify True SymmetricPolynomial[4, {a, b, c, d, e, f}] == Total[Times @@@ Subsets[{a, b, c, d, e, f}, {4}]] // Simplify True Bob Hanlon On Tue, May 29, 2012 at 5:48 AM, Harvey P. Dale <hpd1 at nyu.edu> wrote: > If I have a list and want to sum the products of each possible > grouping of two elements in the list, this program will do that: > > Total[Times @@@ Subsets[{a, b, c}, {2}]] > > Is there any other, shorter, built-in Mathematica object that will > produce the same result? > > Thanks. > > Harvey

**References**:**Sum of Products***From:*"Harvey P. Dale" <hpd1@nyu.edu>