Received 13 November 2015; accepted 7 March 2016; published 10 March 2016

1. Introduction
The concept of n-Lie algebra over a field K, n an integer ≥2, introduced by Fillipov [1] , is a generalization of the concept of Lie algebra over a field K, which corresponds to the case where n = 2. A structure of n-Lie algebra over a K-vector space W, is the given of an alternating multilinear mapping of degree n

verifying the identity

for all
. This identity is called Jacobi identity of n-Lie algebra w [1] [2] .
A derivation of an n-Lie algebra
is a K-linear map

such that

for all
.
The set of all derivations of a n-Lie algebra W is a K-Lie algebra denoted by
.
If
is a n-Lie algebra, then for all
, the map

is a derivation of
.
When A is a commutative algebra, with unit 1A over a commutative field K of characteristic zero, and when M is a A-module, a linear map

is a differential operator of order ≤1 [3] [4] if, for all a and b belonging to A,

When
, we have the usual notion of derivation from A into M.
We denote by
the A-module of differential operator of order ≤1 from A into M and by
the A-module of differential operator of order ≤1 on A (M = A).
The aim of this work is to define the notion of r-Jacobi algebra and to construct the canonical form associated with this r-Jacobi algebra.
In the following, A denotes a unitary commutative algebra over a commutative field K of characteristic zero with unit 1A and
the module of Kähler differential of A and
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the canonical derivation [3] [4] .
2. Structure of Jacobi Algebra of Order r ≥ 1
A-Module A × ΩK(A)
Proposition 1 [3] The map
is a differential operator of order ≤1. Moreover the image of
generates the A-module
.
The pair
has the following universal property [3] [5] [6] : for all A-module M and for all differential operator of order ≤1
![]()
there exists an unique A-linear map
![]()
such that
![]()
Moreover, the map
![]()
is an isomorphism of A-modules.
For all integer
, we say that an alternating K-multilinear map
![]()
is a alternating p-differential operator if for all
, the map
![]()
is a alternating differential operator of order ≤ 1 for all
.
We denote by
, the A-module of alternating A-multilinear maps of degree p from
into M and
, the A-module of alternating p-differential operators from A into M.
One notes
![]()
such that
![]()
for all
.
When
is the A-exterior algebra of the A-module
the differential operator
![]()
can be extended into a differential operator again noted
![]()
of degree +1 and of square 0. Thus, the pair
is a differential complex [3] .
For all A-module M and for all alternating p-differential operator
![]()
there exists an unique alternating A-multilinear map of degree p
![]()
such that
![]()
Thus, the existence of an unique A-linear map
![]()
such that
![]()
for all
elements of A when the map
![]()
is a alternating p-differential operator. Moreover, the map
![]()
is an isomorphism of A-modules [3] .
3. Structure of r-Jacobi Algebra
We say that a commutative algebra with unit A on a commutative field K of characteristic zero, is a r-Jacobi algebra,
an integer, if A is provided with a structure of 2r-Lie algebra over K of bracket
such that for all
the map
![]()
is a differential operator of order ≤1.
Proposition 2 When A is a r-Jacobi algebra, then there exist an unique A-linear map
![]()
such that, for all ![]()
![]()
Proof. The map
![]()
is an alternating
-differential operator. Thus deduced the existence and the uniqueness of the A-linear map
![]()
such that
![]()
That ends the proof.
Canonical form Associated with a r-Jacobi Algebra
In what follows, A is a r-Jacobi algebra.
Theorem 3 The map
![]()
is an alternating 2r-differential operator and induces an alternating A-multilinear mapping and only one of degree 2r
![]()
such that
![]()
Proof. As the map
![]()
is a A-differential operator of order ≤ 1 and the map
![]()
is an alternating
-differential operator.
The unique A-alternating multinear map of degree 2r
![]()
induce an unique A-linear map
![]()
such that
![]()
for all ![]()
We say that
is the canonical form associated with the r-Jacobi algebra A.
Corollary 1 For all ![]()
![]()
for any
.
Acknowledgements
The author thanks Prof. E. Okassa for his remarks and sugestions.