MHB Solve the Sequence Challenge: Find the Missing Digit & a Term

AI Thread Summary
The discussion revolves around a sequence with initial terms $1, 94095, 5265679$, where participants are tasked with finding the missing digit in the 50th term and the corresponding term in the sequence. One participant shares their solution, indicating that the sixth term can be derived by reversing the digits of $b_6$, resulting in $10642473952$. There is a light-hearted exchange about mistakes made in the calculations, with gratitude expressed towards another member for pointing out errors. Additionally, there are friendly mentions of coffee, enhancing the camaraderie among participants. The conversation blends mathematical problem-solving with a social atmosphere.
anemone
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There is a sequence which has the first 3 terms listed as $1,\,94095,\,5265679\cdots$.

The 50th term has all but one digit. If the missing digit is $a$, find the $a$th term from this sequence.
 
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My solution:

Rewrite the sequence by reversing the digits of the numbers listed in the given sequence, we have:

$1,\,59049,\,9765625,\cdots=1^{10},\,3^{10},\,5^{10},\,\cdots$ with its general term defined as $b_n=(2n-1)^{10}$.

So, $b_{50}=(2(50)-1)^{10}=99^{10}=90438207500880449001$ and the missing digit is $a=6$.

Thus, the sixth term of this sequence is the reversed order from $b_6=(2(6)-1)^{10}=25937424601$, i.e. 10642473952.
 
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[sp]So to get the sixth term of the original sequence, you should reverse the digits of $b_6$ to get $10642473952$. (Wink) (Bigsmile) [/sp]
 
Opalg said:
[sp]So to get the sixth term of the original sequence, you should reverse the digits of $b_6$ to get $10642473952$. (Wink) (Bigsmile) [/sp]

Thank you so very much, Opalg for pointing out one most obvious careless stupid mistake of mine, hehehe...since today I have made two cups of coffee for kaliprasad and MarkFL, I'm sorely tempted to make you too another cup of coffee, hehehe...

bcf2d989c859616a1785f945a42e155f.jpg
 
anemone said:
Thank you so very much, Opalg for pointing out one most obvious careless stupid mistake of mine, hehehe...since today I have made two cups of coffee for kaliprasad and MarkFL, I'm sorely tempted to make you too another cup of coffee, hehehe...
Mmmm... just what I like best. As it happens, we visited Bettys of Harrgate today, to buy some of their Java Kalibaru coffee. So we'll think of you as we drink it. (Mmm)
 
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