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Restricted Left-truncatable primes

Restricted Left-truncatable prime is a prime number which, in a given base, contains no 0, and if the leading leftmost digit is successively removed, then all resulting numbers are prime and if all of its left extensions are composite i.e. there is no other left-truncatable prime of which this prime is the left-truncated "tail".

Thus 7939 is a restricted left-truncatable prime because the nine 5-digit numbers ending in 7939 are all composite, whereas 3797 is a left-truncatable prime that is not restricted because 33797 is also prime.

There are 1442 restricted left-truncatable primes.

First 20: 2, 5, 773, 3373, 3947, 4643, 5113, 6397, 6967, 7937, 15647, 16823, 24373, 33547, 34337, 37643, 56983, 57853, 59743, 62383

Checkout list of first: 10, 50 restricted left-truncatable primes. You can also check all restricted left-truncatable primes.

Checkout restricted left-truncatable primes up to: 100, 500, 1000, 10000.

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