{ "id": "1010.1420", "version": "v3", "published": "2010-10-07T12:57:23.000Z", "updated": "2013-12-29T23:22:02.000Z", "title": "On a continued fraction expansion for Euler's constant", "authors": [ "Khodabakhsh Hessami Pilehrood", "Tatiana Hessami Pilehrood" ], "journal": "J. Number Theory 133 (2013) 769-786", "categories": [ "math.NT", "math.CO" ], "abstract": "Recently, A. I. Aptekarev and his collaborators found a sequence of rational approximations to Euler's constant $\\gamma$ defined by a third-order homogeneous linear recurrence. In this paper, we give a new interpretation of Aptekarev's approximations in terms of Meijer $G$-functions and hypergeometric-type series. This approach allows us to describe a very general construction giving linear forms in 1 and $\\gamma$ with rational coefficients. Using this construction we find new rational approximations to $\\gamma$ generated by a second-order inhomogeneous linear recurrence with polynomial coefficients. This leads to a continued fraction (though not a simple continued fraction) for Euler's constant. It seems to be the first non-trivial continued fraction expansion convergent to Euler's constant sub-exponentially, the elements of which can be expressed as a general pattern. It is interesting to note that the same homogeneous recurrence generates a continued fraction for the Euler-Gompertz constant found by Stieltjes in 1895.", "revisions": [ { "version": "v3", "updated": "2013-12-29T23:22:02.000Z" } ], "analyses": { "subjects": [ "11J70", "11B37", "11B65", "33C60", "33F10" ], "keywords": [ "eulers constant", "rational approximations", "linear recurrence", "non-trivial continued fraction expansion convergent", "first non-trivial continued fraction expansion" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1010.1420H" } } }