A sequence of natural numbers is determined by the following formula, A[n+1] = a[n] + f(n) Where f(n) is the product of digits in a[n]. Is there an a[1] such that the above sequence is unbounded?

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Guest Message by DevFuse

# An unbounded sequence?

Started by BMAD, Jan 28 2014 10:15 PM

2 replies to this topic

### #1

Posted 28 January 2014 - 10:15 PM

### #2

Posted 02 February 2014 - 02:41 PM

Spoiler for looks like

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### #3

Posted 02 February 2014 - 02:46 PM

your logic is sound and the last of your explanation is on the correct track

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