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Number of primes between p and p+8 if p is prime, i.e., number of primes between 8+A023202(n) and A023202(n).
0

%I #11 Jul 29 2017 17:14:46

%S 2,2,2,1,1,1,1,1,0,2,1,1,1,2,1,1,1,0,0,0,1,0,0,0,1,1,1,1,1,0,0,0,0,0,

%T 2,0,0,0,1,1,1,0,0,0,1,1,1,1,1,0,0,1,2,0,0,0,1,1,1,0,0,2,0,0,2,1,0,0,

%U 0,0,1,1,1,0,0,1,1,0,0,0,1,0,1,0,0,0,1,0,0,0,0,2,1,1,0,2,0,1,1,0,0,0,1,0,1

%N Number of primes between p and p+8 if p is prime, i.e., number of primes between 8+A023202(n) and A023202(n).

%e a(n)=0,1,2 correspond to {p,p+8} prime-pairs either consecutive or pairs with various d-patterns as follows:

%e a(n)=0 to 89[8]97; a(n)=1 for 29[2,6]37, 53[6,2];

%e a(n)=2 for 101[2,4,2]109 and once to 3[2,2,4]11.

%t cp[x_,y_] := Count[Table[PrimeQ[i],{i,x,y}],True] Do[s=Prime[n]; s1=Prime[n+1]; If[PrimeQ[s+d],k=k+1; Print[cp[s+1,s+d-1]]],{n,1,1000}]; k

%Y Cf. A023302, A046133, A048136, A052165.

%K nonn

%O 1,1

%A _Labos Elemer_, Jul 29 2003