用线圈的自感系数£来表示载流线圈磁场能燈的公式（）

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30391' and id < 2456877 and id<>'2456877' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30391' and id > 2456877 and id<>'2456877' order by id asc limit 5