The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A077985 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A077985

Expansion of 1/(1 + 2*x - x^2).
(history; published version)

#67 by N. J. A. Sloane at Thu Feb 02 15:30:37 EST 2023

STATUS

proposed

approved

#66 by Stefano Spezia at Thu Feb 02 09:17:33 EST 2023

STATUS

editing

proposed

#65 by Stefano Spezia at Thu Feb 02 09:17:05 EST 2023

LINKS

<a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (-2,1).

<a href="/index/Lu#Lucas">Index to Lucas sequences</a>, (-2,-1)

STATUS

proposed

editing

#64 by Stefano Spezia at Wed Feb 01 14:34:37 EST 2023

STATUS

editing

proposed

#63 by Stefano Spezia at Wed Feb 01 14:34:17 EST 2023

FORMULA

E.g.f.: exp(-x)*(2*cosh(sqrt(2)*x) - sqrt(2)*sinh(sqrt(2)*x))/2. - Stefano Spezia, Feb 01 2023

STATUS

proposed

editing

Discussion

Wed Feb 01

14:34

Stefano Spezia: Yes. Thanks. Fixed

#62 by Stefano Spezia at Wed Feb 01 14:07:08 EST 2023

STATUS

editing

proposed

Discussion

Wed Feb 01

14:26

Michel Marcus: parentheses problem ?

#61 by Stefano Spezia at Wed Feb 01 13:58:32 EST 2023

CROSSREFS

Cf. A123335, A175181, A251733.

#60 by Stefano Spezia at Wed Feb 01 13:57:37 EST 2023

FORMULA

E.g.f.: exp(-x)*(2*cosh(sqrt(2*x) - sqrt(2)*sinh(sqrt(2)*x))/2. - Stefano Spezia, Feb 01 2023

STATUS

approved

editing

#59 by Charles R Greathouse IV at Thu Sep 08 08:45:08 EDT 2022

PROG

(MAGMAMagma) I:=[1, -2]; [n le 2 select I[n] else -2*Self(n-1)+Self(n-2): n in [1..35]]; // Vincenzo Librandi, Jan 21 2017

Discussion

Thu Sep 08

08:45

OEIS Server: https://oeis.org/edit/global/2944

#58 by R. J. Mathar at Sat Jul 15 12:17:15 EDT 2017

STATUS

editing

approved