Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: "greedy egyptian fraction expansion"
Displaying 1-6 of 6 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A118323 (Greedy) Egyptian fraction expansion of Catalan constant. +20
31
2, 3, 13, 176, 36543, 1394774578, 12493702893882521837, 265316559833226727589598741150947701321 (list; graph; listen)
OFFSET

1,1

LINKS

Eric Weisstein's World of Mathematics, Egyptian Fraction

EXAMPLE

Catalan constant = 1/2 + 1/3 + 1/13 + 1/176 + 1/36543 + ...

MATHEMATICA

a = {}; k = N[Catalan, 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. A006752.

Cf. A006752, A104338, A014538, A153069, A153070, A054543. - Stuart Clary (clary(AT)uakron.edu), Dec 17, 2008

Sequence in context: A137459 A072162 A113785 this_sequence A113494 A139520 A132535

Adjacent sequences: A118320 A118321 A118322 this_sequence A118324 A118325 A118326

KEYWORD

nonn

AUTHOR

Eric Weisstein (eric(AT)weisstein.com), Apr 23, 2006

A118324 (Greedy) Egyptian fraction expansion of ln(2). +20
26
2, 6, 38, 6071, 144715221, 58600453312405245, 28261174043083404192255923187258021, 1350299665604204277005894785275782053022737307184211775676631561245153 (list; graph; listen)
OFFSET

1,1

LINKS

Eric Weisstein's World of Mathematics, Egyptian Fraction

EXAMPLE

ln(2) = 1/2 + 1/6 + 1/38 + 1/6071 + 1/144715221 + ...

MATHEMATICA

lst={}; k=N[Log[2], 1000]; Do[s=Ceiling[1/k]; AppendTo[lst, s]; k=k-1/s, {n, 12}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Nov 02 2009]

PROGRAM

(PARI) x=log(2); for (k=1, 8, d=ceil(1/x); x=x-1/d; print(d)) [From Jaume Oliver Lafont (joliverlafont(AT)gmail.com), Feb 24 2009]

CROSSREFS

Cf. A002162.

Sequence in context: A057297 A005530 A072191 this_sequence A060421 A054970 A120492

Adjacent sequences: A118321 A118322 A118323 this_sequence A118325 A118326 A118327

KEYWORD

nonn

AUTHOR

Eric Weisstein (eric(AT)weisstein.com), Apr 23, 2006

EXTENSIONS

a(8) from Jaume Oliver Lafont (joliverlafont(AT)gmail.com), Feb 24 2009

A118325 (Greedy) Egyptian fraction expansion of frac(sqrt(3)) = sqrt(3)-1. +20
25
2, 5, 32, 1249, 5986000, 438522193400489, 3126430743599145840898147625516, 10008815260914521335142941393259537613217919681721512170785592 (list; graph; listen)
OFFSET

1,1

LINKS

Eric Weisstein's World of Mathematics, Egyptian Fraction

EXAMPLE

sqrt(3)-1 = 1/2 + 1/5 + 1/32 + 1/1249 + 1/5986000 + ...

MATHEMATICA

lst={}; k=N[(Sqrt[3]-1), 1000]; Do[s=Ceiling[1/k]; AppendTo[lst, s]; k=k-1/s, {n, 12}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Nov 02 2009]

CROSSREFS

Cf. A002194.

Sequence in context: A019036 A005636 A067299 this_sequence A019037 A019038 A114793

Adjacent sequences: A118322 A118323 A118324 this_sequence A118326 A118327 A118328

KEYWORD

nonn

AUTHOR

Eric Weisstein (eric(AT)weisstein.com), Apr 23, 2006

A123180 Even positions of Sylvester's sequence A000058; the denominators of the (greedy) Egyptian fraction expansion of Cahen's constant. +20
1
2, 7, 1807, 10650056950807 (list; graph; listen)
OFFSET

0,1

REFERENCES

E. Cahen, (1891). "Note sur un developpement des quantites numeriques, qui presente quelque analogie avec celui en fractions continues". Nouvelles Annales de Mathematiques 10: 508-514.

LINKS

Cahen's constant

FORMULA

a(n) = a(n-1)(a(n-1)-1)(a(n-1)(a(n-1)-1)+1)+1

CROSSREFS

Cf. A000058, A006279, A006280, A006281, A118227.

Sequence in context: A082891 A000653 A128847 this_sequence A138198 A106023 A152181

Adjacent sequences: A123177 A123178 A123179 this_sequence A123181 A123182 A123183

KEYWORD

easy,nonn

AUTHOR

David Eppstein (eppstein(AT)ics.uci.edu), Oct 03 2006

A157193 Greedy Egyptian fraction expansion for 4/Pi +20
1
1, 4, 44, 1953, 4179942, 42836179578838, 3958573977160882295479936105, 36328295343356352083453782833218820307659379901717630389 (list; graph; listen)
OFFSET

0,2

COMMENT

Sum_{n>=0}1/a(n)=4/Pi

Truncating the series to three terms yields the convergent 22/7 as an approximation to Pi:

1+1/4+1/44=14/11=4/(22/7)

LINKS

Wikipedia, Greedy algorithm for Egyptian fractions

PROGRAM

(PARI) x=4/Pi; for (k=0, 7, d=ceil(1/x); x=x-1/d; print(d, ", "))

CROSSREFS

Cf. A088538, A154956, A156618.

Sequence in context: A155556 A127635 A134174 this_sequence A024254 A167781 A075029

Adjacent sequences: A157190 A157191 A157192 this_sequence A157194 A157195 A157196

KEYWORD

frac,nonn

AUTHOR

Jaume Oliver Lafont (joliverlafont(AT)gmail.com), Feb 24 2009

A157718 Greedy Egyptian fraction expansion of log(3). +20
1
1, 11, 130, 91827, 42593758221, 2068726045016880942060, 20697114911379630588051784011292634933847536, 83276947012925347630278047002339585844748738907354795550015802020488552337404880\ 3963217 (list; graph; listen)
OFFSET

0,2

LINKS

Wikipedia, Greedy algorithm for Egyptian fractions

EXAMPLE

log(3) = Sum_{n>=0} 1/a(n) = 1/1 + 1/11 + 1/130 + 1/91827 + 1/42593758221 + ...

PROGRAM

(PARI) x=log(3); for (k=1, 8, d=ceil(1/x); x=x-1/d; print(d, ", "))

CROSSREFS

Cf. A058962, A154920, A157024, A002391, A118324.

Sequence in context: A024144 A015602 A015603 this_sequence A046210 A100757 A099677

Adjacent sequences: A157715 A157716 A157717 this_sequence A157719 A157720 A157721

KEYWORD

frac,nonn

AUTHOR

Jaume Oliver Lafont (joliverlafont(AT)gmail.com), Mar 04 2009

page 1

Search completed in 0.006 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | The OEIS Foundation | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified February 9 11:24 EST 2010. Contains 172296 sequences.


AT&T Labs Research