1,1

Primes that are both left-truncatable and right-truncatable in base 5.

Table of n, a(n) for n=1..5.

The prime 67 is 232 in base 5. Truncating on the left, we obtain 32 (which is 17 in base 10) and 2, both of which are prime. Truncating on the right, we obtain 23 (which is 13 in base 10) and 2 again. Therefore 232 is in the sequence.

Sequence in context: A328940 A024764 A213971 * A176892 A109615 A101001

Adjacent sequences: A024770 A024771 A024772 * A024774 A024775 A024776

nonn,base,fini,full

David W. Wilson

approved