Brain Teasers
Missing Number: 1, 6, 18...
What is the next number in this sequence?
1, 6, 18, 40, 35, 66, 112, 176, 117, 190, 286, 408, ???
1, 6, 18, 40, 35, 66, 112, 176, 117, 190, 286, 408, ???
Hint
Think about figurate or polygonal numbers.Answer
247. It is the 13th pentagonal number.1 = The 1st pentagonal number
6 = The 2nd hexagonal number
18 = The 3rd heptagonal number
40 = The 4th Octagonal number
The sequence then repeats itself to form a pattern with 5th pentagonal number, 6th hexagonal number, 7th heptagonal number, 8th octagonal number etc.
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