login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A131918 Continued fraction expansion of 1 / (1 - gamma - ln(3/2)) - 54, where gamnma is the Euler-Mascheroni constant. 3
3, 1, 2, 1, 5, 11, 7, 6, 1, 2, 6, 1, 10, 15, 7, 1, 11, 12, 1, 1, 4, 3, 1, 1, 9, 3, 4, 10, 4, 1, 1, 26, 1, 1, 8, 10, 1, 2, 1, 1, 1, 2, 2, 1, 1, 3, 1, 3, 3, 1, 1, 1, 2, 1, 1, 3, 1, 1, 1, 2, 4, 2, 1, 49, 7, 1, 2, 1, 1, 2, 16, 1, 283, 1, 1, 5, 1, 1, 1, 2, 1, 30, 19, 1, 11, 2, 5, 10, 3, 1, 4, 1, 6, 2, 19, 1, 1 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Decimal expansion is A131917. Abstract: An algebraic transformation of the DeTemple-Wang half-integer approximation to the harmonic series produces the general formula and error estimate for the Ramanujan expansion for the n-th harmonic number into negative powers of the n-th triangular number. We also discuss the history of the Ramanujan expansion for the n-th harmonic number as well as sharp estimates of its accuracy, with complete proofs and we compare it with other approximative formulas.

LINKS

Mark B. Villarino, Ramanujan's Harmonic Number Expansion into Negative Powers of a Triangular Number. Constant occurs in Theorem 7 (DeTemple-Wang), formula (1.14), page 6.

FORMULA

(54 ln(3/2) + 54 gamma - 53)/(1 - ln(3/2) - gamma) = 1 / (1 - gamma - ln(3/2)) - 54, where Martin Fuller simplifies the constant which Villarino showed was implicitly given by DeTemple and Wang.

EXAMPLE

3.73929751945... = 3 + 1/1+ 1/2+ 1/1+ 1/5+ 1/11+ 1/7+ 1/6+ 1/1+ 1/2+ 1/6+ 1/1+ 1/10+ 1/15+ 1/7+ 1/1+ 1/11+ 1/12+ 1/1+ 1/1+ 1/4+ 1/3+ 1/1+ 1/1+ 1/9+ 1/3+ 1/4+ 1/10+ 1/4+ 1/1+ 1/1+ 1/26+ 1/1+ 1/1+ 1/8+ 1/10+ 1/1+ 1/2+ 1/1+ 1/1+ 1/1+ 1/2+ 1/2+ 1/1+ 1/1+ 1/3+ 1/1+ 1/3+ 1/3+ 1/1+ 1/1+ 1/1+ 1/2+ 1/1+ 1/1+ 1/3+ 1/1+ 1/1+ 1/1+ 1/2+ 1/4+ 1/2+ 1/1+ 1/49+ 1/7+ 1/1+ 1/2+ 1/1+ 1/1+ 1/2+ 1/16+ 1/1+ 1/283+ 1/1+ 1/1+ 1/5+ 1/1+ 1/1+ 1/1+ 1/2+ 1/1+ 1/30+ 1/19+ 1/1+ 1/11+ 1/2+ 1/5+ 1/10+ 1/3+ 1/1+ 1/4+ 1/1+ 1/6+ 1/2+ 1/19+ 1/1+ 1/1+ 1/3+ 1/2+ 1/1+ . . .

CROSSREFS

Cf. A001008, A001620, A131915, A131916, A131917.

Sequence in context: A059807 A135261 A102774 * A010123 A039620 A008296

Adjacent sequences:  A131915 A131916 A131917 * A131919 A131920 A131921

KEYWORD

cofr,easy,nonn

AUTHOR

Jonathan Vos Post (jvospost3(AT)gmail.com), Jul 27 2007

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 17 19:13 EST 2012. Contains 206085 sequences.