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MathGroup Archive 2005

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Re: challenge problem

  • To: mathgroup at smc.vnet.net
  • Subject: [mg61291] Re: [mg61219] challenge problem
  • From: Zhengji Li <zhengji.li at gmail.com>
  • Date: Fri, 14 Oct 2005 05:56:10 -0400 (EDT)
  • References: <200510130539.BAA04503@smc.vnet.net> <a6e65e8d0510131901t7a5eee74q74469892d454bf5@mail.gmail.com>
  • Sender: owner-wri-mathgroup at wolfram.com

A further look at the lucky sevens showing that they are in the form:
7, 77, 777, ....

So we can get the result just in a blink:
Sum[7 FromDigits@Table[1, {i}], {i, 11}]
86419753077

--
Li Zhengji
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If all you have is a hammer, everything is a nail.
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