A088712 Primes which when concatenated with the previous prime form a new prime.

5, 53, 59, 67, 137, 179, 211, 223, 239, 263, 359, 541, 593, 613, 631, 653, 659, 757, 809, 977, 997, 1009, 1109, 1129, 1237, 1399, 1559, 1783, 1931, 1979, 1993, 2309, 2339, 2347, 2411, 2683, 2879, 3061, 3203, 3271, 3613, 3643, 3767, 4001

Offset: 1

Author

Chuck Seggelin (barkeep(AT)plasteredDragon.com), Oct 15 2003

Keywords

• base
• nonn

Examples

			a(2) = 53 because 53 concatenated with the preceding prime (47) yields 5347 which is also prime.
		

Crossrefs

Cf. A088784.

Formula

If isprime(p(n) & p(n-1)) then sequence.add(p(n))