A280357 Primes formed from concatenating nextprime(n) and n.

53, 2927, 3733, 4139, 5347, 5351, 5953, 6761, 6763, 9791, 113111, 127123, 131129, 137131, 149143, 179173, 191189, 211199, 223211, 223217, 223219, 233231, 239233, 239237, 263257, 277273, 281279, 307301, 331319, 347341, 359353, 359357, 419417, 431423, 431429, 479473

Offset: 1

Author

K. D. Bajpai, Jan 04 2017

Keywords

• nonn
• base

Comments

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

Examples

			53 is in the sequence because it is prime formed from concatenation of 5 and 3, where 5 is next prime after 3.
3733 is in the sequence because it is prime formed from concatenation of 37 and 33, where 37 is next prime after 33.
		

Links

• K. D. Bajpai, Table of n, a(n) for n = 1..10000

Crossrefs

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

Programs

Magma

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

Mathematica

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