The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A282132

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

A282132

Imaginary part of n!*Sum_{k=1..n} i^(k-1)/k, where i is sqrt(-1).
(history; published version)

#15 by N. J. A. Sloane at Sun Feb 19 13:51:29 EST 2017

STATUS

proposed

approved

#14 by Daniel Suteu at Sun Feb 19 13:13:42 EST 2017

STATUS

editing

proposed

#13 by Daniel Suteu at Sun Feb 19 13:13:19 EST 2017

CROSSREFS

Cf. A016655, A024167.

STATUS

proposed

editing

#12 by Daniel Suteu at Sun Feb 19 10:19:06 EST 2017

STATUS

editing

proposed

Discussion

Sun Feb 19

13:07

Michel Marcus: Then you could add xref A016655 (see my new comment there) ?

#11 by Daniel Suteu at Sun Feb 19 10:18:47 EST 2017

FORMULA

a(n) ~ log(sqrt(2)) * n!.

STATUS

approved

editing

#10 by N. J. A. Sloane at Mon Feb 06 20:14:15 EST 2017

STATUS

proposed

approved

#9 by Daniel Suteu at Mon Feb 06 16:19:10 EST 2017

STATUS

editing

proposed

#8 by Daniel Suteu at Mon Feb 06 16:18:52 EST 2017

FORMULA

a(1) = 0, a(n+1) = a(n) * (n+1) + n! * Imsin(i^Pi*n), where Im(z/2) is the imaginary part of z.

STATUS

proposed

editing

#7 by Daniel Suteu at Mon Feb 06 16:05:07 EST 2017

STATUS

editing

proposed

#6 by Daniel Suteu at Mon Feb 06 16:04:20 EST 2017

FORMULA

a(1) = 0, a(n+1) = a(n) * (n+1) * a(+ n) + ! * Im(i^n * n!), where Im(z) is the imaginary part of z.