A note on a result by Hamada on minihypers
نویسندگان
چکیده
Hamada [Bull. Osaka Women’s Univ. 24:1–47, 1985; Discrete Math. 116:229-268, 1993] characterized the non-weighted minihypers having parameters ( ∑h i=1 vλi+1, ∑h i=1 vλi ; t, q) with t > λ1 > λ2 > · · · > λh ≥ 0. This result has been generalized in [Des. Codes Cryptogr. 45:123-138,2007] where it was proved that a weighted ( ∑h i=1 vλi+1, ∑h i=1 vλi ; t, q)-minihyper F, with k − 1 > λ1 > λ2 > · · · > λh ≥ 0, is a sum of the characteristic functions of spaces of dimension λ1, . . . , λh. In this note, we prove that we can relax further the restrictions on the integers λi by allowing r(q)− 1 equalities in the chain of strict inequalities λ2 > . . . > λh.
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