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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A132120 Decimal expansion of the constant obtained through Pierce retro-expansion of the prime sequence. 2
3, 6, 2, 3, 0, 6, 2, 2, 2, 3, 6, 6, 4, 9, 8, 0, 4, 8, 7, 9, 8, 6, 2, 6, 3, 7, 2, 2, 2, 4, 0, 9, 3, 4, 6, 1, 8, 1, 1, 1, 7, 9, 8, 5, 8, 5, 3, 4, 4, 2, 0, 9, 9, 9, 7, 5, 9, 9, 5, 1, 0, 1, 7, 0, 2, 7, 8, 4, 1, 8, 8, 6, 3, 0, 6, 8, 9, 6, 5, 0 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Paolo P. Lava, Table of n, a(n) for n = 0..1000

Eric Weisstein's World of Mathematics, Pierce Expansion, MathWorld.

FORMULA

Equals sum_{i=1..infinity} (-1)^(i+1)/A002110(i).

EXAMPLE

0.3623062223664980487986263722240934618111798585344209997599510170278418863068...

MAPLE

Digits := 80 : a := 0 : for i from 1 to 100 do a := a+(-1.0)^(i-1)/mul(ithprime(j), j=1..i) ; print(a) ; od:

PROG

(PARI) P=1; -sumalt(n=1, (-1)^n/P*=prime(n)) \\ Charles R Greathouse IV, Oct 03 2016

CROSSREFS

Cf. A064648.

Sequence in context: A058099 A292789 A124085 * A021280 A282728 A193537

Adjacent sequences:  A132117 A132118 A132119 * A132121 A132122 A132123

KEYWORD

cons,nonn

AUTHOR

R. J. Mathar, Oct 31 2007

EXTENSIONS

Corrected last entry by Paolo P. Lava, May 28 2013

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 26 16:47 EDT 2019. Contains 323597 sequences. (Running on oeis4.)