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Template:Sequence of the Day for March 3

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Intended for: March 3, 2013

Timetable

  • First draft entered by Alonso del Arte on February 13, 2012
  • Draft reviewed by Daniel Forgues on March 3, 2016
  • Draft to be approved by February 3, 2013
Yesterday's SOTD * Tomorrow's SOTD

The line below marks the end of the <noinclude> ... </noinclude> section.



A061278
a (n) = 5 a (n  −  1)  −  5 a (n  −  2) + a (n  −  3)
, with
a (1) = 1
and
a (k ) = 0
if
k   ≤   0
.
{ 1, 5, 20, 76, 285, 1065, 3976, 14840, ... }
Gil Broussard noticed that these are “numbers
n
such that
n  (n + 1) =
x

i  = 1
 (n + i )
= n  x +
x

i  = 1
i
for some
x
,” except of course for the first term.