A083989 Concatenation of prime k and its 10's complement is a prime.

3, 7, 17, 23, 29, 31, 41, 43, 53, 67, 71, 83, 109, 127, 139, 151, 173, 179, 197, 211, 229, 263, 271, 281, 307, 359, 463, 547, 557, 569, 587, 593, 673, 677, 683, 691, 701, 719, 727, 757, 769, 823, 839, 881, 883, 887, 907, 937, 983, 997, 1087, 1103, 1171, 1181

Offset: 1

Author

Amarnath Murthy, May 23 2003

Keywords

• base
• nonn

Examples

			43 belongs to this sequence as 4357 is also a prime.
		

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A083990, A089186.

Programs

Maple

g:= proc(n) local c; c:= 10^(1+ilog10(n))-n; n*10^(1+ilog10(c))+c end proc:
select(t -> isprime(t) and isprime(g(t)), [seq(i,i=3..10000,2)]); # Robert Israel, Jul 03 2024

Extensions

More terms from Jason Earls, Jun 01 2003