While interesting, that is property of decimal notation rather than the integer number itself. In hexadecimal notation, 2013 is the first (since 2007 -> 0x7d7)

While interesting, that is property of decimal notation rather than the integer number itself. In hexadecimal notation, 2013 is the first (since 2007 -> 0x7d7) with duplicate digits ;-) 1987 -> 0x7c3 1988 -> 0x7c4 1989 -> 0x7c5 ... 2007 -> 0x7d7 2008 -> 0x7d8 2009 -> 0x7d9 2010 -> 0x7da 2011 -> 0x7db 2012 -> 0x7dc 2013 -> 0x7dd