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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A069139 Egyptian fraction for square root of 1/2. 24
2, 5, 141, 68575, 32089377154, 1644444237306316731482, 65593236350142721999718859354569312622907814, 55836140966941396682452590821074724094286247680248793718758259857815239633935672711970868 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

LINKS

Index entries for sequences related to Egyptian fractions

Eric Weisstein's World of Mathematics, Egyptian Fraction

FORMULA

a(n) =ceiling[1/sqrt(2)-Sum_i{i<n}1/a(i)]

EXAMPLE

a(3)=68575 since sqrt(1/2)=0.707106781186..., 1/2+1/5+1/141+1/68574=0.707106781368... (which is too much) and 1/2+1/5+1/141+1/68575=0.707106781155... (which is not too much).

MATHEMATICA

a = {}; k = N[1/Sqrt[2], 1000]; Do[s = Ceiling[1/k]; AppendTo[a, s]; k = k - 1/s, {n, 1, 10}]; a [From Artur Jasinski (grafix(AT)csl.pl), Sep 22 2008]

CROSSREFS

Cf. A006487.

Sequence in context: A145620 A130412 A175525 * A155762 A062611 A041505

Adjacent sequences:  A069136 A069137 A069138 * A069140 A069141 A069142

KEYWORD

nonn

AUTHOR

Henry Bottomley (se16(AT)btinternet.com), Apr 08 2002

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 14 15:39 EST 2012. Contains 205635 sequences.