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1, 3, 7, 11, 17, 23, 31, 50, 60, 71, ...

Series teasers are where you try to complete the sequence of a series of letters, numbers or objects.

 

Puzzle ID:#39351
Fun:*** (2.13)
Difficulty:*** (3.07)
Category:Series
Submitted By:shenqiangAcn****!!

 

 

 



What are the next five terms in this sequence?

1, 3, 7, 11, 17, 23, 31, 50, 60, 71, 83, 97, 111, 127, 153, 171, 190, 210, 231, 263, 287, 311, 337, 373, ___, ___, ___, ___, ___, ...



Answer

501, 530, 570, 601, 633.

In all the natural numbers that don't contain the "unlucky" digit 4, the first one is 1, skip one and get 3, skip two and get 7, skip three and get 11, and so on.

It can also be said that these are the triangular numbers in the nonary system, except that the digits 0, 1, 2, 3, 5, 6, 7, 8, 9 are being used to represent 0, 1, 2, 3, 4, 5, 6, 7, 8.

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Comments

jamesbondAsg*
Nov 25, 2007

could u explain that again please???
lukeschettAus*
Nov 25, 2007

I don't get it.
rockstar1234567Aca*
Nov 27, 2007

uh..
petey127Aus*
Jan 06, 2008

say wha?
andrew000000Aau*
Jan 15, 2008

what the eff??
mousechicksus*
Apr 21, 2008

how is four unlucky. this is for someone with advanced knowledge of math.

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