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Concatenation of n-th prime and n in decimal notation.
12

%I #23 Sep 08 2022 08:45:07

%S 21,32,53,74,115,136,177,198,239,2910,3111,3712,4113,4314,4715,5316,

%T 5917,6118,6719,7120,7321,7922,8323,8924,9725,10126,10327,10728,10929,

%U 11330,12731,13132,13733,13934,14935,15136,15737,16338,16739,17340

%N Concatenation of n-th prime and n in decimal notation.

%H Reinhard Zumkeller, <a href="/A075110/b075110.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A000040(n)*10^(A004216(n)+1) + n.

%t Table[FromDigits[Join[IntegerDigits[Prime[n]], IntegerDigits[n]]], {n, 40}] (* _Vincenzo Librandi_, Mar 24 2019 *)

%o (Haskell)

%o a075110 n = read $ show (a000040 n) ++ show n :: Integer

%o -- _Reinhard Zumkeller_, Jul 08 2014

%o (PARI) a(n) = eval(Str(prime(n), n)); \\ _Michel Marcus_, Mar 24 2019

%o (Magma) [Seqint(Intseq(n) cat Intseq(NthPrime(n))): n in [1..46]]; // _Vincenzo Librandi_, Mar 24 2019

%Y Cf. A045532.

%K nonn,base

%O 1,1

%A _Reinhard Zumkeller_, Sep 03 2002