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Category: | Math |

Submitted By: | javaguru |

Fun: | (2.47) |

Difficulty: | (3.21) |

What characteristic do these three 12-digit numbers share with each other, but with no other 12-digit number?

100307124369

111824028801

433800063225

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Posted by markmonnin | 01/07/09 |

That's amazing trivia! :o | |

Posted by javaguru | 01/07/09 |

Thanks! I've never seen these before, but I was wondering if there were any that fit this pattern, so I wrote a program to find them. Since then I submitted several series to the Online Encyclopedia of Integer Sequences (OEIS) about these numbers. (See http:// www.research.att.com/ ~njas/sequences/A153745.) | |

Posted by SweetiePi | 02/15/09 |

Wow. Cool! :D | |

Posted by Jimbo | 03/29/09 |

Very interesting but you surely aren't expecting us to get all of those properties without looking at the answer , are you? :roll: | |

Posted by javaguru | 03/29/09 |

I agree this is more of a puzzle than a teaser, but I think it's possible to get the answer. If you observe that the numbers are all squares and that their digital sums are all squares, I think it's possible to get the next step with the sum of the digit pairs. :) |

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