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Table of n, a(n) for n=1..53.
If t=10, then t1 = 101 (prime).
If t=180, then t1 = 1801 (prime).
If t=420, then t1 = 4201 (prime).
Sequence in context: A197705 A187205 A104045 * A108777 A000132 A217073
Adjacent sequences: A102543 A102544 A102545 * A102547 A102548 A102549
Parthasarathy Nambi, Feb 24 2005