OFFSET
1,2
EXAMPLE
For a(22)=819 the difference is 10443 and no other n <= 827 exceeds that difference.
MATHEMATICA
NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; d = 0; k = 1; Do[ While[f = NextPrim[10^k] - 10^k; d >= f, k++ ]; d = f; Print[k], {n, 1, 50}]
CROSSREFS
KEYWORD
hard,nonn,more
AUTHOR
Robert G. Wilson v, Jun 18 2002
STATUS
approved