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A088712
Primes which when concatenated with the previous prime form a new prime.
3
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
1,1
FORMULA
If isprime(p(n) & p(n-1)) then sequence.add(p(n))
EXAMPLE
a(2) = 53 because 53 concatenated with the preceding prime (47) yields 5347 which is also prime.
CROSSREFS
Cf. A088784.
Sequence in context: A216459 A107803 A255579 * A257667 A045711 A090153
KEYWORD
base,nonn
AUTHOR
Chuck Seggelin (barkeep(AT)plasteredDragon.com), Oct 15 2003
STATUS
approved