ClearAll[Primediffs] p = Prime[Range[PrimePi[10^6]]]; Primediffs[seq_] := {First[#], Last[#], Length[#]} &[p[[#1 ;; #2 + 1]] & @@@ SequencePosition[Differences[p], seq]] Primediffs[{2}] Primediffs[{1}] Primediffs[{2, 2}] Primediffs[{2, 4}] Primediffs[{4, 2}] Primediffs[{6, 4, 2}]