--playlist-items オプションを使ったらこうなりました。

$ youtube-dl --playlist-items 1,4-46 https://www.youtube.com/watch?v=1oe5x0mAg3A&;list=PLTa0n5b1eRqrpbf2rH8B9hLCi-IjM3VaW
[1] 8325
$ [youtube] 1oe5x0mAg3A: Downloading webpage
[youtube] 1oe5x0mAg3A: Downloading video info webpage
WARNING: Requested formats are incompatible for merge and will be merged into mkv.
[download] Destination: 第140回 日商簿記3級 総評-1oe5x0mAg3A.f137.mp4
[download] 100% of 513.51MiB in 02:13
[download] Destination: 第140回 日商簿記3級 総評-1oe5x0mAg3A.f251.webm
[download] 100% of 23.99MiB in 00:05
[ffmpeg] Merging formats into "第140回 日商簿記3級 総評-1oe5x0mAg3A.mkv"
Deleting original file 第140回 日商簿記3級 総評-1oe5x0mAg3A.f137.mp4 (pass -k to keep)
Deleting original file 第140回 日商簿記3級 総評-1oe5x0mAg3A.f251.webm (pass -k to keep)

[1]+ Done youtube-dl --playlist-items 1,4-46 https://www.youtube.com/watch?v=1oe5x0mAg3A