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Table of n, a(n) for n=1..53.
The 10th regular prime is 29. The 10th irregular prime is 257. 257-29 = 228, the 10th entry in the table.
Sequence in context: A267999 A157352 A176255 * A048033 A254366 A242291
Adjacent sequences: A090874 A090875 A090876 * A090878 A090879 A090880
Cino Hilliard, Feb 13 2004