login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A299632 Decimal expansion of 2*W(e/2), where W is the Lambert W function (or PowerLog); see Comments. 3
1, 3, 7, 0, 1, 5, 3, 8, 8, 4, 3, 0, 9, 1, 8, 7, 8, 9, 2, 0, 5, 6, 4, 9, 8, 9, 6, 1, 0, 7, 5, 2, 6, 0, 3, 7, 6, 8, 2, 8, 1, 1, 1, 4, 3, 1, 3, 6, 1, 6, 4, 1, 0, 6, 7, 0, 8, 1, 9, 6, 0, 3, 0, 9, 9, 7, 5, 0, 0, 7, 7, 5, 7, 0, 2, 2, 3, 7, 6, 2, 9, 5, 6, 2, 3, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The Lambert W function satisfies the functional equations

W(x) + W(y) = W(x*y(1/W(x) + 1/W(y)) = log(x*y)/(W(x)*W(y)) for x and y greater than -1/e, so that 2*W(3/2) =W(e^2/2)/(1/W(e/2)) = 2 - log(4) - 2 log(W(e/2)).  See A299613 for a guide to related sequences.

LINKS

Table of n, a(n) for n=0..85.

Eric Weisstein's World of Mathematics, Lambert W-Function

EXAMPLE

2*W(e/2) = 1.3701538843091878920564989610752603...

MATHEMATICA

w[x_] := ProductLog[x]; x = E/2; y = E/2; u = N[w[x] + w[y], 100]

RealDigits[u, 10][[1]]  (* A299632 *)

PROG

(PARI) 2*lambertw(exp(1)/2) \\ Altug Alkan, Mar 13 2018

CROSSREFS

Cf. A299613, A299632.

Sequence in context: A261873 A293525 A016617 * A249186 A118746 A181913

Adjacent sequences:  A299629 A299630 A299631 * A299633 A299634 A299635

KEYWORD

nonn,cons,easy

AUTHOR

Clark Kimberling, Mar 13 2018

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 August 5 22:07 EDT 2020. Contains 336214 sequences. (Running on oeis4.)