Sunday, 14 February 2010


I've programmed a small web application in PHP to get automatically the BibTeX citation of any sequence in the The On-Line Encyclopedia of Integer Sequences.

If you follow this link: OEIS2BibTeX or just click on the above image, then you must enter the desired sequence ID to get the BibTeX citation data, that you can easily copy to your .bib file.

As I begun to learn PHP yesterday´s evening, and this is my first PHP programming, you can guess that this code must have more than one bug.

The citation is done using the @MISC BibTeX entry, that uses as Required fields: none, and as Optional fields: AUTHOR, TITLE, HOWPUBLISHED, MONTH, YEAR, NOTE.

The AUTHOR field contains the OEIS Sequence Author.

HOWPUBLISHED contains the url to the sequence in the OEIS Wiki, and it is assumed to be used with the $latex \LaTeX$ hyperref packages

MONTH and YEAR are not yet used, and the field NOTE includes the Description of the sequence.

If this small application is used in combination with the BibTeX2HTML it is very fast to reuse the same bibliography data in your web, or in your $latex \LaTeX$ document.

All the PHP archives can be downloaded and changed if desired.

The reference [1] is an example of how does the Plain format works.

References and Archives:
[1] Clark Kimberling. The On-Line Encyclopedia of Integer Sequences. A045051. Numbers n with property that in base 4 representation the numbers of 0's and 2's are 2 and 4, respectively.
[2] Andrew Roberts. Bibtex entry and field types.
[3] Psychedelic Geometry.PHP file. OEIS2BibTeX.php.
[4] Psychedelic Geometry.PHP file. default.php, feb 2010.
[5] Psychedelic Geometry. OEIS2BibTeX web site., feb 2010.