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Primes formed from concatenating nextprime(n) and n.
2

%I #48 Jan 05 2017 03:25:01

%S 53,2927,3733,4139,5347,5351,5953,6761,6763,9791,113111,127123,131129,

%T 137131,149143,179173,191189,211199,223211,223217,223219,233231,

%U 239233,239237,263257,277273,281279,307301,331319,347341,359353,359357,419417,431423,431429,479473

%N Primes formed from concatenating nextprime(n) and n.

%C Alternatively: Primes formed from reverse concatenation of n and nextprime(n).

%H K. D. Bajpai, <a href="/A280357/b280357.txt">Table of n, a(n) for n = 1..10000</a>

%e 53 is in the sequence because it is prime formed from concatenation of 5 and 3, where 5 is next prime after 3.

%e 3733 is in the sequence because it is prime formed from concatenation of 37 and 33, where 37 is next prime after 33.

%t Select[Table[FromDigits[Join[IntegerDigits[NextPrime[n]], IntegerDigits[n]]],{n,1000}], PrimeQ]

%o (Magma) [p : n in[1 .. 200] | IsPrime(p) where p is Seqint(Intseq(n) cat Intseq(NextPrime(n)))];

%Y Cf. A000040, A084667, A084669, A151799, A151800, A280388.

%K nonn,base

%O 1,1

%A _K. D. Bajpai_, Jan 04 2017