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A153414 Larger of twin prime pairs such that p1*p2+average_of_twin_prime_pair=prime. 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

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

MATHEMATICA

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 *)

CROSSREFS

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

Sequence in context: A025095 A025114 A090935 * A284405 A232237 A104815

Adjacent sequences:  A153411 A153412 A153413 * A153415 A153416 A153417

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Dec 25 2008

STATUS

approved

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Last modified May 23 18:08 EDT 2022. Contains 353993 sequences. (Running on oeis4.)