cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A083825 a(1) = 12; then numbers obtained at every stage of division by 9 in the following process. multiply by 9, reverse the digits, divide by 9, reverse the digits, multiply by 9, reverse the digit, divide by 9, ...

Original entry on oeis.org

12, 89, 32, 78, 43, 67, 54, 56, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65
Offset: 1

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Author

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 09 2003

Keywords

Comments

The interesting pattern of terminating at 65 after which every term is 65 is visible. 89 onwards alternate terms are obtained by subtracting 11 and 32 onwards alternate terms are obtained by adding 11 and both terminate at 65. Conjecture: Every such sequence for an n-digit number not divisible by 10 terminates in another n-digit number. Let it be t(n), then one also gets t(10k) =t(k). E.g. t(12) = 65. Subsidiary sequence:(1) a(n) = t(n), a(10k) = a(k). (2). The index of the first occurrence of t(n). A measure of the length of the cycle.

Examples

			*12--->108--->801--->*89--->98--->882---288-->*32--->23--->207--->702--->*78--->87--->783--->387--->*43--->34--->306--->603--->*67--->76...
		

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