Table of n, a(n) for n=1..60.
If n=1, then 1000^n - 3 = 1000^1 - 3 = 997 which is a prime, so the first term is 1.
Cf. A105069, A105068.
Sequence in context: A134834 A035583 A145178 * A215182 A214906 A274228
Adjacent sequences: A105076 A105077 A105078 * A105080 A105081 A105082
Parthasarathy Nambi, Apr 06 2005