A153378 -id:A153378 - cp's OEIS frontend

A153413 Smaller of twin prime pairs such that p1*p2+average_of_twin_prime_pair=prime.

3, 5, 29, 59, 137, 179, 239, 419, 617, 1049, 1607, 1697, 1787, 2267, 2309, 2729, 3257, 3389, 3527, 3767, 4157, 4217, 4337, 4799, 5639, 5867, 6659, 6689, 6869, 6959, 7487, 7547, 7589, 8537, 8627, 8969, 9629, 9857, 9929, 10457, 11117, 11969, 12539, 13337

Offset: 1

Vladimir Joseph Stephan Orlovsky, Dec 25 2008

nonn

3*5+4=19 prime, 5*7+6=41 prime, 29*31+30=929 prime, ...

Cf. A099349, A153374, A153375, A153376, A153377, A153378, A153379, A153406, A153407, A153408, A153409, A153410

lst={};Do[p1=Prime[n];p2=Prime[n+1];If[p2-p1==2,a=p1*p2+(p1+1);If[PrimeQ[a],AppendTo[lst,p1]]],{n,7!}];lst

A153414 Larger of twin prime pairs such that p1*p2+average_of_twin_prime_pair=prime.

Original entry on oeis.org

5, 7, 31, 61, 139, 181, 241, 421, 619, 1051, 1609, 1699, 1789, 2269, 2311, 2731, 3259, 3391, 3529, 3769, 4159, 4219, 4339, 4801, 5641, 5869, 6661, 6691, 6871, 6961, 7489, 7549, 7591, 8539, 8629, 8971, 9631, 9859, 9931, 10459, 11119, 11971, 12541, 13339

Offset: 1

Vladimir Joseph Stephan Orlovsky, Dec 25 2008

nonn

3*5+4=19 prime, 5*7+6=41 prime, 29*31+30=929 prime, ...

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Cf. A099349, A153374, A153375, A153376, A153377, A153378, A153379, A153406, A153407, A153408, A153409, A153410, A153413

lst={};Do[p1=Prime[n];p2=Prime[n+1];If[p2-p1==2,a=p1*p2+(p1+1);If[PrimeQ[a],AppendTo[lst,p2]]],{n,7!}];lst
Transpose[Select[Select[Partition[Prime[Range[1600]],2,1],Last[#]- First[#] == 2&], PrimeQ[Times@@#+Mean[#]]&]][[2]] (* Harvey P. Dale, Jan 23 2012 *)

cp's OEIS Frontend

A153413 Smaller of twin prime pairs such that p1*p2+average_of_twin_prime_pair=prime.

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