The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A009088 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A009088

Expansion of e.g.f. x*cos(tanh(x)), odd powers only.
(history; published version)

#25 by Michael Somos at Mon Jul 30 00:39:09 EDT 2018

STATUS

proposed

approved

#24 by G. C. Greubel at Thu Jul 26 01:57:06 EDT 2018

STATUS

editing

proposed

Discussion

Thu Jul 26

02:10

Michel Marcus: offset : can be 1 if indices are seen as 2*n-1 or 0 if seen as 2*n+1 , no ?

#23 by G. C. Greubel at Thu Jul 26 01:56:50 EDT 2018

NAME

Expansion of e.g.f. x*cos(tanh(x)), even odd powers only.

PROG

(PARI) x='x+O('x^5060); v=Vec(serlaplace(x*cos(tanh(x)))); vector((#v-1)\2, n, v[2*n-1]) \\ G. C. Greubel, Jul 25 2018

STATUS

proposed

editing

#22 by Muniru A Asiru at Wed Jul 25 05:12:48 EDT 2018

STATUS

editing

proposed

Discussion

Wed Jul 25

05:27

Muniru A Asiru: Output is 0, 1, 0, -3, 0, 45, 0, -1239, 0, 54873, 0, ...?

Thu Jul 26

00:21

Michel Marcus: replace even with odd in name ?

#21 by Muniru A Asiru at Wed Jul 25 05:02:01 EDT 2018

MAPLE

seq(coeff(series(factorial(n)*x*cos(tanh(x)), x, n+1), x, n), n=1..30, 2); # Muniru A Asiru, Jul 25 2018

STATUS

proposed

editing

Discussion

Wed Jul 25

05:12

Muniru A Asiru: Offset is 1? For even powers only.

#20 by Michel Marcus at Wed Jul 25 02:37:17 EDT 2018

STATUS

editing

proposed

#19 by Michel Marcus at Wed Jul 25 02:37:15 EDT 2018

NAME

Expansion of e.g.f. x*cos(tanh(x)), even terms powers only.

STATUS

proposed

editing

#18 by G. C. Greubel at Wed Jul 25 01:44:53 EDT 2018

STATUS

editing

proposed

#17 by G. C. Greubel at Wed Jul 25 01:44:36 EDT 2018

NAME

Expansion of e.g.f. x*cos(tanh(x))*x, even terms only.

LINKS

G. C. Greubel, <a href="/A009088/b009088.txt">Table of n, a(n) for n = 0..239</a>

PROG

(PARI) x='x+O('x^50); v=Vec(serlaplace(x*cos(tanh(x)))); vector(#v\2, n, v[2*n-1]) \\ G. C. Greubel, Jul 25 2018

STATUS

approved

editing

#16 by Jon E. Schoenfield at Sat Apr 01 11:23:31 EDT 2017

STATUS

editing

approved