32/21 |5 -1 0 -1>
729.2191 cents
https://en.xen.wiki/w/File:Jid_32_21_pluck_adu_dr220.mp3 sound sample
32/21, the septimal super-fifth, is the interval between 9/8 and 12/7. It is 64/63 sharp of 3/2, and so is equated to 3/2 in temperaments such as pajara, superpyth or augene which temper 64/63 out.