DEL

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DEL

Abbreviation for:
deletion
deltoid
delusion
Departmental Expenditure Limit
References in periodicals archive ?
Proof of the Corollary: The symmetry in q and t comes from a general property of the nabla operator, which is easy to show: nabla applied to any Schur function is symmetric in q and t.
where [e.sub.1], [e.sub.2], [e.sub.3] are quaternion imaginary units obeying (with ordinary quaternion symbols: [e.sub.1] = i, [e.sub.2] = j, [e.sub.3] = k): [i.sub.2] = [j.sub.2] = [k.sub.2] = -1, ij = -ji = k, jk = -kj = i, ki = -ik = j and quaternion Nabla operator is defined as [13]:
In order to generalize equation (9) to biquaternion version (BQSE), we use first quaternion Nabla operator (5), and by noticing that [DELTA] [equivalent to] [nabla][nabla], we get