Output a sequence of all the primes that are of the following form:
123...91011...(n-1)n(n-1)..11109...321
. That is, ascending decimal numbers up to some n
, followed by a descending tail, all concatenated.
Background
Recently, Numberphile posted a video about primes that follow this pattern.
Output
1 -> 12345678910987654321 (n=10)
2 -> 123...244524462445...321 (n=2446)
No more terms are known, but it's likely that there are infinitely many.