OFFSET
1,2
EXAMPLE
For a(19)=411, the difference is 4433 and no other n <= 540 exceeds that difference.
MATHEMATICA
PrevPrim[n_] := Block[{k = n - 1}, While[ !PrimeQ[k], k-- ]; k]; d = 0; k = 1; Do[ While[f = 10^k - PrevPrim[10^k]; d >= f, k++ ]; d = f; Print[k], {n, 1, 50}]
CROSSREFS
KEYWORD
base,nonn
AUTHOR
EXTENSIONS
Edited and extended by Robert G. Wilson v, Jun 18 2002
a(23) from Robert G. Wilson v, Jan 10 2007
STATUS
approved