Let pn denote the n-th prime and, for m≥1, write
Hm:=n→∞liminf(pn+m−pn)
for the least limit point of the gaps between primes m apart. Maynard [May15] proved that Hm is finite for every m, with Hm≪m3e4m; the growth rate in m is exponential in all bounds known, and the exponent for bounded gaps between many primes is
C88b:=m→∞limsupmlogHm,
equivalently the least c for which Hm≪εexp((c+ε)m) holds for every ε>0.
The case m=1 is recorded separately as C88a; note that C88b is insensitive to any finite number of Hm, so the two are genuinely independent quantities.