A077391 Smallest n-digit prime which leaves a prime at every step if most significant digit and least significant digit are deleted until a one digit or two digit prime is obtained, or 0 if no such prime exists.
2, 11, 127, 1021, 10313, 100237, 1002931, 10002331, 100023331, 1000023337, 10000239937, 100000233397, 1000002339937, 10000002339931, 100000139991331, 1000000023399331, 10000000233993397, 100000000293999997
Offset: 1
Examples
a(6) = 100237: this is the smallest 6-digit number such that deleting MSD and LSD yields prime at every step, i.e. 100237, 0023, 02 all are primes.
Crossrefs
Cf. A077390.
Extensions
More terms from Daniel Starodubtsev, May 05 2020
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