R' U' F L2 F' L2 R D2 U2 B2 U2 L D2 L' B R D R' U' F' D' U2 B2 R' U' F
L B D F R2 B' R2 L' D2 L F2 B R2 L2 B' D2 R2 L2 B2 U2
L B D // 4-2 EO (3)
F R2 B’ {L U2 L} // DR, 0c0 4e (9)
extend: {...} = L’ R2 D2 L // 0c0 4e (10)
[B’ R2 L2 B’ // HTR (14)
U2 R2 L2 F2] U2 // S slice (19)
{...} = F2 B L2 R2 B’ D2 L2 R2 B2 // solve
solution: L B D F R2 B’ L’ R2 D2 L F2 B L2 R2 B’ D2 L2 R2 B2 U2 // 20
The initial 9 move DR is 20 optimal as well and I found it later on
After L U2 L:
(B2 U2 F’ R2 L2 F’) // HTR (15)
(U2 B2 U2 F2 D2) // finish (20)
other DRs:
(B’ L B D)
(B’ U2 B2 R2 B R) // 4a2 2e (10), 22 optimal
B’ L B D
B U2 L2 R2 B R // 2c4 (10), 23 optimal
B L B D
B2 L’ B’ U2 F2 R // 2c4 (10) with 2 variations, 24 optimal
and some in 11, at least it’s all I managed to find before the 20s.R' U' F L D' B D2 L' R' B2 U2 L B2 D L' R2 D' U2 L R' B' R' U' F
F2 D2 L2 U2 D2 B2 R L2 U2 L F2 U R D' R L2 B D' F' D
(D’ F D B’) // 7-8 EO (4) (L2 R’ D R’ U’) // DR, 4b2 2e (9), extended 4b2 4e in 8 (F2 [R’ F2 L]) // HTR (13) (B2 U2 D2 L2 D2 F2) // M slice (19) [...] = L’ U2 R’ L2 // solve solution: F2 D2 L2 U2 D2 B2 R L2 U2 L F2 U R D’ R L2 B D’ F’ D // 20 other DRs: (D’ F D B’) (R U R’ D) // mentioned 4b2 4e (8), 21 optimal (B’ D’ F) (D) RZP 7-8 (R’ D R’ U) // 2c4 (8), 21 optimal (D’ F D B’) (R U R’ D) // 4b2 4e (8), 21 optimal (D’ F D B’) (R’ D R’ U) // 2c4 (8), 21 optimal (U2 B D’ F) (D’ F2 L’ D L’ U) // 2c4 (10), 23 optimal and at least 3 10+5s from the (B’ D’ F) EO.
R' U' F U' L2 R2 B R2 B F' L2 F R2 F2 R D2 R2 D' F R' U R' U' F
B R2 D F2 B' R2 B2 D2 L U2 D B2 D2 L F2 D2 R L D2 R2
B R2 D B // 4-4 EO (4) B2 F2 R2 B2 D2 L D // DR, 4a1 4e (10) U2 B2 D2 [R // HTR (14) U2 F2 L2] D2 R2 // M slice (19) [...] = L F2 D2 R L // solve sol: B R2 D B’ F2 R2 B2 D2 L D U2 B2 D2 L F2 D2 R L D2 R2 // 20 Backup 21: B R2 D B F2 B2 L2 F2 U2 L U // DR, 4a1 4e (10) (B2 D2 R’) // HTR (13) (F2 L2 D2 L2 D2 B2 L2 B2) // finish (21) and then I realised that there was another 10+1 before it was too late. other DRs: U D2 L2 F D2 L2 B2 R L2 D // 0c0 4e (10) U D2 L2 F D2 R2 F2 R L2 U // and 0c0 4e (10), 21 optimal each which I did find (R B D’ R) (B2 U’ D F2 D F) // 4b2 4e (10), 23 optimal (R B D’ R) (B2 L2 U’ L2 D2 F) // 4b2 4e (10) with 2 variations, 21 optimal with 4q U’ R2 B R L D2 L2 F2 R’ L2 D // 0c0 4e (11) U’ R2 B R L D2 R2 B2 R’ L2 U // and 0c0 4e (11), 23 optimal each