How to with single ffmpeg command (= single seek through the input file) cut into segments and concatenate some of them into several output files?

Question

Starting with a single input video (with no audio), suppose I'm interested in time segments [a,b], [b,c], [d, e], [f,g], [h,i], ... where the letters are some timestamps. I am looking for an ffmpeg command that will create output files where each one is a concatenation of specified time segments, say 1.mp4 is [a,b]+[b,c], 2.mp4 is [d, e]+[f,g]+[h,i], ... such that the input video is seeked through only once; that is, seeking is O(1) w.r.t. the number of segments and/or output files and so seeking time is solely dependent on the length of the input video, not how it's cut. Thanks.