Every pair of hexagrams, ie every odd-numbered hexagram with the even-numbered one that follows it, carries some un-pin-downable*feeling of ‘inspiration and manifestation’ or ‘question and response’ or ‘yang and yin’. Only I just wonder whether there might be a more specific patterns in the 7s and 8s…
Hexagram 7, the Army – and being within it. Hexagram 8, Seeking Union – looking at the terrain from outside to see where you belong. The general and the king.
Hexagram 17, Following – being within the flow. Hexagram 18, Corruption – examining and changing the flow from outside.
Hexagram 27, Nourishment – a containing structure. Hexagram 28, Great Exceeding – ‘the noble one stands alone without fear…’ (Daxiang). Incubating and hatching.
Hexagram 37, People in the Home. Hexagram 38, Opposing. ‘Opposing means outside. People in the Home means inside.’ (Zagua) Two different points of view on the same structure.
Hexagram 47, Confined, the view from inside an enclosed, oppressive space. Hexagram 48, the Well, reaching down into a dark, enclosed space from above to draw out the water.
Hexagram 57, Subtly Penetrating (into). Hexagram 58, Opening. ‘Opening: seeing. Subtly Penetrating: hidden away.’ (Zagua) These two begin to feel like a simple ‘key’ that unlocks the whole sequence.
Are you seeing what I’m seeing – inside and outside? (And if so, is there anything half so clear for other pairs?)

This is an interesting pattern. The #7/8 position in each decade is quite important. I think it has something to do with the ritual connotations of the calendar signs for 7/8, geng and xin. The distribution of wind in these hexagrams is worth noticing.
May I add something about #17/18? Sui as "following" is also implying the Gu hexagram in several ways. Of course, it mentions a mountain whereas Gu has the mountain trigram. But the character for sui is connected to gu in a very specific way, because sui includes meanings such as spoiled meat and improper offerings just as gu does. The character of sui is part of the expression for "bone marrow," so it definitely has a connection with meat and offerings similar to gu.