A236452 - OEIS

%I #10 Sep 26 2019 08:44:58

%S 3,1,2,2,1,1,1,0,4,0,1,2,3,0,2,1,0,6,0,0,0,0,2,0,2,2,0,4,0,2,0,4,0,0,

%T 1,0,0,3,3,0,1,7,0,1,0,0,0,0,4,0,0,0,0,2,4,0,1,1,2,3,1,0,0,2,0,3,6,0,

%U 0,1,2,2,1,0,0,2,0,0,0,1,0,1,0,4,1,2,3

%N Number of primes between successive Ramanujan primes.

%C The Ramanujan primes are given in A104272.

%H T. D. Noe, <a href="/A236452/b236452.txt">Table of n, a(n) for n = 1..10000</a>

%e A104272(n) = 2, 11, 17, 29, 41, 47, 59, 67, 71, ...

%e a(1) = 3 because there are 3 primes between 2 and 11;

%e a(2) = 1 because there is 1 prime between 11 and 17;

%e a(3) = 2 because there are 2 primes between 17 and 29;

%e a(8) = 0 because there are no prime between 67 and 71.

%t lst={}; nn=1000; R=Table[0, {nn}]; s=0; Do[If[PrimeQ[k], s++]; If[PrimeQ[k/2], s--]; If[s<nn, R[[s+1]]=k], {k, Prime[3*nn]}]; R=R+1; Do[p=0; Do[If[PrimeQ[a], p++ ], {a, R[[n]]+1, R[[n+1]]-1}]; AppendTo[lst, p], {n, 100}]; lst

%Y Cf. A104272.

%K nonn

%O 1,1

%A _Michel Lagneau_, Jan 26 2014