実行結果例

integration[1] // Timing
{0., 1}

integration[2] // Timing
{0.842, 3/4}

integration[3] // Timing
{13.385, 2/3}

integration[4] // Timing
{143.177, 115/192}

integration[1, 1/3] // Timing
{0., 1}

integration[2, 1/3] // Timing
{0.843, 13/18}

integration[3, 1/3] // Timing
{14.352, 31/54}

integration[4, 1/3] // Timing
{157.42, 11/24}