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A227878 Primes occurring twice in A051701. 2
3, 19, 41, 43, 71, 83, 101, 109, 151, 167, 199, 227, 229, 257, 281, 283, 311, 313, 349, 383, 401, 443, 461, 463, 487, 503, 571, 601, 617, 641, 643, 677, 727, 757, 829, 857, 859, 881, 883, 911, 937, 941, 971, 1033, 1063, 1091, 1093, 1123, 1187, 1217, 1231 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Consider five consecutive primes p1..p5: (p3 is a term of this sequence) iff (p2-p1 > p3-p2 and p5-p4 > p4-p3).

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

PROG

(Haskell)

a227878 n = a227878_list !! (n-1)

a227878_list = f a051701_list where

   f (p:ps@(_:p':_)) = if p == p' then p : f ps else f ps

CROSSREFS

Sequence in context: A114704 A167053 A131542 * A042371 A141644 A141170

Adjacent sequences:  A227875 A227876 A227877 * A227879 A227880 A227881

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Oct 25 2013

STATUS

approved

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Last modified June 6 14:04 EDT 2020. Contains 334827 sequences. (Running on oeis4.)