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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.)