The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A076455

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A076455

Sum of numbers that can be written as t*n + u*(n+1) for nonnegative integers t,u in exactly two ways.
(history; published version)

#17 by Charles R Greathouse IV at Thu Sep 08 08:45:07 EDT 2022

PROG

(MAGMAMagma) [n*(n+1)*(4*n^2+2*n-1)/2: n in [1..50]]; // Vincenzo Librandi, Dec 30 2013

Discussion

Thu Sep 08

08:45

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

#16 by Bruno Berselli at Tue May 22 10:28:31 EDT 2018

STATUS

editing

approved

#15 by Bruno Berselli at Tue May 22 10:28:28 EDT 2018

FORMULA

G.f.: x*(5 + 32*x + 11*x^2)/(1 - x)^5.

a(n) = n*(n + 1)*(4*n^2 + 2*n - 1)/2.

G.f.: x*(5+32*x+11*x^2)/(1-x)^5.

KEYWORD

easy,nonn

nonn,easy

STATUS

approved

editing

#14 by N. J. A. Sloane at Mon Mar 02 16:08:49 EST 2015

AUTHOR

_Floor van Lamoen (fvlamoen(AT)hotmail.com), _, Oct 13 2002

Discussion

Mon Mar 02

16:08

OEIS Server: https://oeis.org/edit/global/2352

#13 by Ralf Stephan at Tue Dec 31 03:40:44 EST 2013

STATUS

reviewed

approved

#12 by Joerg Arndt at Mon Dec 30 04:01:42 EST 2013

STATUS

proposed

reviewed

#11 by Joerg Arndt at Mon Dec 30 04:01:38 EST 2013

STATUS

editing

proposed

#10 by Joerg Arndt at Mon Dec 30 04:01:33 EST 2013

FORMULA

a(n) = n*(n+1)*(4*n^2+2*n-1)/2. G.f.: x*(5+32*x+11*x^2)/(1-x)^5.

G.f.: x*(5+32*x+11*x^2)/(1-x)^5.

STATUS

proposed

editing

#9 by Vincenzo Librandi at Mon Dec 30 01:41:39 EST 2013

STATUS

editing

proposed

#8 by Vincenzo Librandi at Mon Dec 30 01:41:22 EST 2013

PROG

(MAGMA) [n*(n+1)*(4*n^2+2*n-1)/2: n in [1..50]]; // Vincenzo Librandi, Dec 30 2013