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User:Philippe Guglielmetti

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I'm a computer scientist, amateur mathematician and blogger.

My main contribution here is a study of frequency of appearance in the OEIS database which led to the discovery of "Sloane's gap" between "interesting" and "uninteresting" integers.

Read the articles on my blog (in French) about this : http://www.drgoulu.com/tag/sloane/

I also successfully submitted A303935 (read the story in french here : https://www.drgoulu.com/2018/06/09/a303935-ma-premiere-sequence-oeis/)

I use the OEIS to check the correcteness of some algorithms in my 'Goulib' Python library available here https://github.com/goulu/Goulib :

  • the math2.py[1] module contains numeric algorithm
  • the Sequence[2] class uses iterators and the itertools2.py[3] module to represent infinite integer sequences
  • the oeis.py[4] module defines many Sequences using OEIS numbering and description
  • the test_oeis.py[5] module automatically downloads the corresponding sequences from the OEIS website (as B-files) and compares the values calculated in 'Goulib' with those stored in the OEIS.

This allowed me to find many bugs in my code ... and a few in the OEIS data:

  • in A121727 the 20th term was wrong
  • in A036275 several terms had a (invisible) initial zero(s). My code[6] correctly puts them at the end. I also extended the table from 500 to 1000 terms.

This article on my blog decribes this : https://www.drgoulu.com/2017/06/26/series-infinies-et-oeis-en-python/

You're most welcome to use and contribute to the Goulib library, especially by defining OEIS Sequences ...