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The number of twin primes between prime(i)*prime(i+1) and prime(i+1)*prime(i+2) where prime(i) and prime(i+1) are twin primes.
1

%I #22 Mar 27 2021 23:28:03

%S 2,3,4,3,5,6,9,11,8,12,24,19,34,14,27,14,28,17,46,26,24,55,28,14,86,

%T 50,38,66,28,67,76,41,64,40,43,93,53,87,67,48,89,66,42,72,69,76,49,76,

%U 42,49,59,73,260,109,145,169,70,137,193,292

%N The number of twin primes between prime(i)*prime(i+1) and prime(i+1)*prime(i+2) where prime(i) and prime(i+1) are twin primes.

%o (PARI) {for(n=1,200, if(prime(n+1)-prime(n)==2, my(a=prime(n)*prime(n+1), b=prime(n+1)*prime(n+2), c=0); for(m=a,b, if(isprime(m)==1&&isprime(m+2)==1, c=c+1)); print1(c, ", ")))}

%Y Cf. A171727, A006094, A001359, A006512, A037074.

%K nonn

%O 1,1

%A _Zhandos Mambetaliyev_, Mar 27 2021