Problem 2040. Additive persistence

Created by Jean-Marie Sainthillier

Solve Later

{"relationships":[{"relationshipType":"http://schemas.mathworks.com/matlab/code/2013/relationships/document","targetMode":"","relationshipId":"rId1","target":"/matlab/document.xml"},{"relationshipType":"http://schemas.mathworks.com/matlab/code/2013/relationships/output","targetMode":"","relationshipId":"rId2","target":"/matlab/output.xml"}],"parts":[{"partUri":"/matlab/document.xml","relationship":[],"contentType":"application/vnd.mathworks.matlab.code.document+xml","content":"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<w:document xmlns:w=\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\"><w:body><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Inspired by Problem 2008 created by Ziko.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>In mathematics, the persistence of a number is the</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:b/></w:rPr><w:t>number of times</w:t></w:r><w:r><w:t> one must apply a given operation to an integer before reaching a fixed point; where further application does not change the number any more (Wikipedia).</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Problem 2008 is an example of multiplicative persistence. Can you code an additive persistence ?</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>2718-&gt;2+7+1+8=18-&gt;1+8=9. So the persistence of 2718 is 2.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>You can use the tips : num2str(666)-'0'=[6 6 6].</w:t></w:r></w:p></w:body></w:document>"},{"partUri":"/matlab/output.xml","contentType":"text/xml","content":"<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\" ?><embeddedOutputs><metaData><evaluationState>manual</evaluationState><layoutState>code</layoutState><outputStatus>ready</outputStatus></metaData><outputArray type=\"array\"/><regionArray type=\"array\"/></embeddedOutputs>"}]}

Solve

Solution Stats

245 Solutions
128 Solvers

Last Solution submitted on Dec 29, 2020

Last 200 Solutions

Problem Comments

1 Comment

1 Comment

Mehmet OZC on 11 Dec 2013

Tip was so instructive... Thanks

Problem Recent Solvers128

Problem Tags

persistence recursion

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Problem 2040. Additive persistence

Solution Stats

Last 200 Solutions

Problem Comments

Problem Recent Solvers128

Suggested Problems

More from this Author43

Problem Tags

Community Treasure Hunt

Problem 2040. Additive persistence

Solution Stats

Last 200 Solutions

Problem Comments

Problem Recent Solvers128

Suggested Problems

More from this Author43

Problem Tags

Community Treasure Hunt

Players