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Praetorian
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took more than 2 mins.
B.

1 and 81 only.
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Virtual
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Hi,

I am not convinced with myself that these are the only 2 solutions of the infinite set of +ve integers.

If anybody finds a way to prove this, please pass it on.

Thanx.


While juggling with this, here is another ques. which got framed.....

How many positive integers are there whose sum of digits is equal to the sum of digits of its squareroot??
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Virtual
Hi,

I am not convinced with myself that these are the only 2 solutions of the infinite set of +ve integers.

If anybody finds a way to prove this, please pass it on.

Thanx.


While juggling with this, here is another ques. which got framed.....

How many positive integers are there whose sum of digits is equal to the sum of digits of its squareroot??


remember , you got to choose from the five choices above. mathematical proofs are good to know , but you got to cautious about that.
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Paul
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Praet, so this means answer is 2? :)
I tried to solve using all square until 16 which I know by heart. I stopped there and realized there were only 2 solutions so far...
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Agreed, proof may not be a good option but how do we know that it may not be 3, 4 or 5 ???

What do i do with such a ques. in actual test ???

ps: BTW, I tried some large integers also and tried to get fix it based on max. 2 digit no., 3 digit no....... and so on.

but no success :(
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Paul
Praet, so this means answer is 2? :)
I tried to solve using all square until 16 which I know by heart. I stopped there and realized there were only 2 solutions so far...


yes, the answer is 2 numbers. i just made this problem a bit harder by including the option of 4 and 5 numbers.

getting problems correct under the time limit is the key.

good job guyz :)



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