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A181981 Smallest prime p such that n primes exist between the twin prime pair (p, p+2) and the next twin prime pair. 3

%I

%S 3,17,41,107,71,2267,1091,461,1319,1151,347,5741,2999,5279,10139,1487,

%T 9461,881,659,13007,9041,15359,8627,28751,83717,13397,18539,14627,

%U 44771,54011,60257,59669,142157,77711,61559,178931,26261,122867,293261,89069,24419

%N Smallest prime p such that n primes exist between the twin prime pair (p, p+2) and the next twin prime pair.

%e a(4)= 71 because the 4 primes 79, 83, 89, 97 exist between (71, 73) and (101,103).

%p A181981 := proc(n)

%p local j,hi,lo ;

%p if n = 0 then

%p 3;

%p else

%p for j from 1 do

%p hi := numtheory[pi](A001359(j+1)) ;

%p lo := numtheory[pi](A006512(j)) ;

%p if hi-lo = n+1 then

%p return A001359(j);

%p end if;

%p end do:

%p end if;

%p end proc: # _R. J. Mathar_, Jul 03 2012

%Y Cf. A001359, A006512, A027833.

%K nonn

%O 0,1

%A _Michel Lagneau_, Jul 03 2012

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Last modified August 10 06:08 EDT 2022. Contains 356029 sequences. (Running on oeis4.)