漂亮的数字串可以有通项公式吗?
04, 07, 05, 09, 02, 06, 08, 01, 03,
05, 08, 06, 10, 03, 07, 09, 02, 04,
06, 09, 07, 11, 04, 08, 10, 03, 05,
07, 10, 08, 12, 05, 09, 11, 04, 06,
08, 11, 09, 13, 06, 10, 12, 05, 07,
09, 12, 10, 14, 07, 11, 13, 06, 08,
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