1-5-7-9-13-15 eikosany
A 15-odd-limit eikosany. This creates a scale of 1 117/112 15/14 9/8 135/112 39/32 9/7 13/10 39/28 117/80 3/2 351/224 13/8 117/70 27/16 195/112 9/5 13/7 15/8 27/14 2/1, with steps of 117/112 40/39 21/20 15/14 91/90 96/91 91/90 15/14 21/20 40/39 117/112 28/27 36/35 105/104 65/63 336/325 65/63 105/104 36/35 28/27. With 4 notes that are close enough to blur into their neighbours, this is not optimal for its size, but it still has 8 notes with perfect fifths above them and no major gaps in the scale, making it quite easy to compose in as long as you don't mind that there are more semiquartal chords available than familiar 5-limit ones.
! 1-5-7-9-13-15_Eikosany.scl ! 1 5 7 9 13 15 3-combination Eikosany 20 ! 75.611 119.442 203.910 323.352 342.482 435.084 454.213 573.656 658.123 701.955 777.566 840.527 889.298 905.865 959.970 1017.596 1071.701 1088.268 1137.039 1200