|
|
A166680
|
|
a(n) = n*(a(n-1)-4), a(0) = 1.
|
|
1
|
|
|
1, -3, -14, -54, -232, -1180, -7104, -49756, -398080, -3582756, -35827600, -394103644, -4729243776, -61480169140, -860722368016, -12910835520300, -206573368324864, -3511747261522756, -63211450707409680
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
LINKS
|
|
|
FORMULA
|
a(n) = n! - 4*floor(e*n!) + 4, n>0. - Gary Detlefs, Jun 19 2010
|
|
MATHEMATICA
|
RecurrenceTable[{a[0]==1, a[n]==n(a[n-1]-4)}, a, {n, 20}] (* Harvey P. Dale, Apr 18 2014 *)
FoldList[#1*#2 - 4 #2 &, 1, Range[50]] (* G. C. Greubel, May 23 2016 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
easy,sign
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|