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 A154530 Primes that are a concatenation of 2*k and 2*k+1 or 2*k and 2*k-1 for some k. 4
 23, 43, 67, 89, 109, 1213, 2221, 2423, 3433, 3637, 4241, 4243, 5051, 5657, 5857, 6263, 6869, 7069, 7877, 7879, 8081, 8887, 9091, 9293, 9697, 10099, 102101, 102103, 108107, 108109, 112111, 114113, 120121, 124123, 126127, 138139, 148147, 150151 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Pierre CAMI, Table of n, a(n) for n=1..10153 EXAMPLE 2*1=2, 2*1+1=3, and 23 the concatenation of 2 and 3 is prime, so a(1)=23 PROG (Haskell) a154530 n = a154530_list !! (n-1) a154530_list = filter ((== 1) . a010051') a248378_list -- Reinhard Zumkeller, Jun 27 2015 CROSSREFS Cf. A133986, A154531, A328903. Cf. A010051, subsequence of A248378. Sequence in context: A306085 A037137 A340136 * A156979 A281226 A158283 Adjacent sequences:  A154527 A154528 A154529 * A154531 A154532 A154533 KEYWORD nonn,base AUTHOR Pierre CAMI, Jan 11 2009 EXTENSIONS Edited by Charles R Greathouse IV, Apr 28 2010 STATUS approved

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Last modified July 26 01:20 EDT 2021. Contains 346294 sequences. (Running on oeis4.)