Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #18 Sep 30 2024 13:04:50
%S 1,2,5,1,1,3,5,3,2,4,7,12,0,1,2,6,3,0,4,0,1,3,2,0,1,3,1,2,2,3,8,1,1,1,
%T 3,3,1,1,1,2,2,2,8,3,4,3,3,4,1,7,2,0,7,1,1,0,4,4,4,4,7,1,12,1,1,1,0,5,
%U 3,2,2,3,1,4,3,2,0,2,4,3,0,9,1,1,1,3,1,1,2,1,2,5,13,0,1,4,6,0,4
%N Number of primes between successive primitive practical numbers. That is, number of primes p such that A267124(n) < p <= A267124(n+1).
%e a(3) = 5 because between the 3rd and 4th primitive practical numbers, namely 6 and 20 there are 5 primes. They are 7, 11, 13, 17 and 19.
%t lst=Last/@ReadList["https://oeis.org/A267124/b267124.txt", {Number, Number}]; seq=Table[PrimePi[lst[[n+1]]]-PrimePi[lst[[n]]], {n, 1, Length@lst-1}]; seq[[1;;100]]
%Y Cf. A000040, A267124.
%K nonn
%O 1,2
%A _Frank M Jackson_, Sep 22 2024