12345...34567 (95-digits)
This number is a prime.
12345 6781234567 8123456781
2345678123 4567812345 6781234567 8123456781 2345678123 4567812345 6781234567
The above ninety-five digit integer represents one of four prime outputs in the initial one thousand terms of the integer sequence 1, 12, 123, 1234, 12345, 123456, 1234567, 12345678, 123456781, 1234567812, 12345678123, etc. as one cycles around the eight hour clock. The other prime outputs among the initial one thousand terms are the four hundred sixty-third, the five hundred twenty-seventh and the six hundred forty-seventh terms of this sequence. It is clear that the reversal of this sequence 8, 87, 876, 8765, 87654, 876543, 8765432, 87654321, 876543218, 8765432187, 87654321876, etc., contains no prime outputs. [Schiffman]
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