The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A078370

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

A078370

a(n) = 4*(n+1)*n + 5.
(history; published version)

#83 by Michael De Vlieger at Thu Feb 23 07:42:27 EST 2023

STATUS

reviewed

approved

#82 by Michel Marcus at Thu Feb 23 00:19:10 EST 2023

STATUS

proposed

reviewed

#81 by Leo Tavares at Wed Feb 22 15:37:15 EST 2023

STATUS

editing

proposed

#80 by Leo Tavares at Wed Feb 22 15:36:57 EST 2023

LINKS

<a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).

#79 by Leo Tavares at Wed Feb 22 15:35:22 EST 2023

LINKS

Leo Tavares, <a href="/A078370/a078370.jpg">Square illustration</a>

FORMULA

a(n) = A016754(n) + 4. - Leo Tavares, Feb 22 2023

CROSSREFS

Cf. A016754.

STATUS

approved

editing

#78 by N. J. A. Sloane at Sun Dec 11 02:37:55 EST 2022

STATUS

editing

approved

#77 by N. J. A. Sloane at Sun Dec 11 02:37:38 EST 2022

COMMENTS

Discriminants Discriminant of the binary quadratic forms y^2 - x*y - A002061(n+1)*x^2. - Klaus Purath, Nov 10 2022

STATUS

proposed

editing

Discussion

Sun Dec 11

02:37

N. J. A. Sloane: "discriminant"

#76 by Klaus Purath at Thu Nov 10 12:37:47 EST 2022

STATUS

editing

proposed

Discussion

Fri Nov 11

13:02

Michel Marcus: we are in A078370, so I don't see why this comment  (whihc uses  A002061(n+1)) ??

14:35

Klaus Purath: All terms are congruent to 1 modulo 4, so they are discriminants.
2 examples: a(2) = 29 is the discriminant of y^2 - x*y - 7*x^2 and 7 = A002061(3). a(6) = 173 is the discriminant of y^2 - x*y - 43*x^2 and 43 = A002061(7).

Tue Nov 15

10:44

Michel Marcus: ok sorry

#75 by Klaus Purath at Thu Nov 10 12:37:21 EST 2022

COMMENTS

Discriminants of the binary quadratic forms y^2 - x*y - A002061(n+1)*x^2. - Klaus Purath, Nov 10 2022

STATUS

approved

editing

#74 by Joerg Arndt at Mon Sep 05 05:19:28 EDT 2022

STATUS

reviewed

approved