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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A012248 Expansion of e.g.f. exp(arcsinh(arcsin(x))). 3
1, 1, 1, 1, 1, 9, 49, 225, 897, 11025, 96801, 893025, 6803457, 108056025, 1275363153, 18261468225, 207592347393, 4108830350625, 60889593787713, 1187451971330625, 17888210916886017, 428670161650355625, 7679611833095218545, 189043541287806830625, 3530100224793651058305 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,6

LINKS

Table of n, a(n) for n=0..24.

FORMULA

E.g.f.: Q(0)-1, where Q(k) =  2 + arcsin(x)/(1 - arcsin(x)/Q(k+1) ); (continued fraction). - Sergei N. Gladkovskii, Dec 19 2013

EXAMPLE

1 + x + 1/2!*x^2 + 1/3!*x^3 + 1/4!*x^4 + 9/5!*x^5...

PROG

(PARI) x = 'x + O('x^30); Vec(serlaplace(exp(asinh(asin(x))))) \\ Michel Marcus, Mar 09 2017

CROSSREFS

Bisections are |A012115(n)| and A001818.

Sequence in context: A228212 A027608 A003297 * A080026 A060867 A192814

Adjacent sequences:  A012245 A012246 A012247 * A012249 A012250 A012251

KEYWORD

nonn

AUTHOR

Patrick Demichel (patrick.demichel(AT)hp.com)

EXTENSIONS

More terms from Michel Marcus, Mar 09 2017

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 November 18 12:16 EST 2019. Contains 329261 sequences. (Running on oeis4.)