105edo is the equal division of the octave into 105 equal parts of 11.429 cents each. It is most notable as a tuning of meantone and in particular higher limit extensions of meantone, as it is the highest edo that strictly fulfills both criteria of meantone - ie, all intervals can be reached by stacking it's best fifth, and stacking four of them equals it's best major third. It tempers out 81/80 in the 5-limit; 81/80, 126/125 and hence 225/224 in the 7-limit; 99/98, 176/175 and 441/440 in the 11-limit; and if we want to push that far, 144/143 in the 13-limit. This is the sharper fifth mapping (aka "huygens") of 11-limit meantone. Script error: No such module "primes_in_edo".

105edo gives the optimal patent val for 11-limit meantone (ie huygens rather than meanpop) and provides a good tuning in the 13-limit, though 74edo is in that case the optimal patent val. 105 is highly composite, being the product 3*5*7 (i. e. (14+1)*14/2) of the three smallest odd primes, with other divisors being 15, 21 and 35. As the common multiple of these three primes and the triangular number closest to 100, 105 is a perfect substitute for it when a "cent" is desired to include them all or be a triangular number.

105edo close-up

C . . Dbb B## . . C# . . Db . . . C## . . D

Since 105edo has a step of 11.429 cents, it also allows one to use its MOS scales as circulating temperaments, which it is the first triangular edo to do.

Circulating temperaments in 105edo
Tones Pattern L:s
5 5edo equal
6 3L 3s 18:17
7 7edo equal
8 1L 7s 14:13
9 6L 3s 12:11
10 5L 5s 11:10
11 6L 5s 10:9
12 9L 3s 9:8
13 1L 12s
14 7L 7s 8:7
15 15edo equal
16 9L 7s 7:6
17 3L 14s
18 15L 3s 6:5
19 10L 9s
20 5L 15s
21 21edo equal
22 17L 5s 5:4
23 13L 10s
24 9L 15s
25 5L 20s
26 1L 25s
27 24L 3s 4:3
28 21L 7s
29 18L 11s
30 15L 15s
31 12L 19s
32 9L 23s
33 6L 27s
34 3L 31s
35 35edo equal
36 33L 3s 3:2
37 31L 6s
38 29L 9s
39 27L 12s
40 25L 15s
41 23L 18s
42 21L 21s
43 19L 24s
44 17L 27s
45 15L 30s
46 13L 33s
47 11L 36s
48 9L 39s
49 7L 42s
50 5L 45s
51 3L 48s
52 1L 51s
53 52L 1s 2:1
54 51L 3s
55 50L 5s
56 49L 7s
57 48L 9s
58 47L 11s
59 46L 13s
60 45L 15s
61 44L 17s
62 43L 19s
63 42L 21s
64 41L 23s
65 40L 25s
66 39L 27s
67 38L 29s
68 37L 31s
69 36L 33s
70 35L 35s
71 34L 37s
72 33L 39s
73 32L 41s
74 31L 43s
75 30L 45s
76 29L 47s
77 28L 49s
78 27L 51s
79 26L 53s
80 25L 55s
81 24L 57s
82 23L 59s
83 22L 61s