OFFSET
1,1
COMMENTS
Inspired by A374350.
EXAMPLE
Although the primes {149, 179, 199, 941, 971, 991} all have prime reversals and their differences are 792, 149 is the least. Therefore a(3) = 149.
MATHEMATICA
a[n_] := Block[{lmt = 2*10^(n -1) +1, mx = 0, p = NextPrime[10^(n -1)], q}, While[p < lmt, q = IntegerReverse@ p; If[ PrimeQ@ q && Abs[p -q] > mx, mx = Abs[p -q]; pq = p]; p = NextPrime@ p]; pq];
CROSSREFS
KEYWORD
base,nonn,more
AUTHOR
Robert G. Wilson v, Jul 06 2024
STATUS
approved