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A084669 Primes which are a concatenation of prime(n) and n. 7
53, 239, 6719, 7321, 15737, 30763, 38977, 41981, 44987, 587107, 661121, 751133, 1051177, 1229201, 1297211, 1303213, 1327217, 1823281, 1913293, 1999303, 2131321, 2179327, 2207329, 2239333, 2371351, 2689391, 2699393, 3067439 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..28.

EXAMPLE

a(2)=239 because prime[9]=23 and concatenation of 23 and 9 is 239 which is prime.

MATHEMATICA

Select[Table[FromDigits[Flatten[{IntegerDigits[Prime[n]], IntegerDigits[n]}]], {n, 1, 500}], PrimeQ]

PROG

(MAGMA) [p: n in [1..500] | IsPrime(p) where p is Seqint(Intseq(n) cat Intseq(NthPrime(n)))]; // Bruno Berselli, Sep 15 2015

CROSSREFS

Cf. A084667.

Subsequence of primes of A075110.

Sequence in context: A053652 A142316 A142026 * A256339 A142357 A142061

Adjacent sequences:  A084666 A084667 A084668 * A084670 A084671 A084672

KEYWORD

nonn,base

AUTHOR

Zak Seidov, Jun 29 2003

STATUS

approved

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Last modified June 19 19:03 EDT 2019. Contains 324222 sequences. (Running on oeis4.)