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A138397 Penta-Primes. Prime Numbers n as a Sum of 5 consecutive prime numbers (four twin primes and single prime number in between) are primes. 1
181, 331, 1381, 6481, 6551, 8069, 10499, 11633, 17669, 17851, 27551, 44249, 45137, 50273, 51437, 68501, 73061, 85999, 90073, 90631, 112997, 115249, 142799, 154303, 186757, 196169, 237019, 238397, 247693, 250027, 266239, 278227, 291899, 337097, 344263, 354677 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

{29, 31} {37} {41, 43} Sum = 181

MATHEMATICA

a={}; Do[p0=Prime[n]; a1=Prime[n-2]; a2=Prime[n-1]; b1=Prime[n+1]; b2=Prime[n+2]; sp=a1+a2+p0+b1+b2; If[PrimeQ[sp]&&a2-a1==2&&b2-b1==2, AppendTo[a, sp]], {n, 3, 10^3}]; a

Select[Total/@Select[Partition[Prime[Range[1000]], 5, 1], #[[2]]-#[[1]]== #[[5]] -#[[4]]==2&], PrimeQ] (* Harvey P. Dale, Aug 26 2019 *)

CROSSREFS

Sequence in context: A168473 A142920 A142058 * A179484 A142258 A323192

Adjacent sequences:  A138394 A138395 A138396 * A138398 A138399 A138400

KEYWORD

nonn,uned

AUTHOR

Vladimir Joseph Stephan Orlovsky, May 08 2008

EXTENSIONS

More terms from Harvey P. Dale, Aug 26 2019

STATUS

approved

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Last modified December 1 22:12 EST 2021. Contains 349435 sequences. (Running on oeis4.)