|
|
A025971
|
|
Expansion of 1/((1-2x)(1-4x)(1-7x)(1-8x)).
|
|
0
|
|
|
1, 21, 287, 3249, 33159, 317457, 2913079, 25951233, 226266887, 1941258033, 16450020951, 138048250977, 1149556141735, 9512774280849, 78317007130103, 642041894674881, 5244884610706503, 42718957418411505, 347070960515299735, 2813803342053741345
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
LINKS
|
|
|
FORMULA
|
a(n) = (5*8^(n+2)-7^(n+3)+10*4^(n+1)-2^(n+1))/15. - Yahia Kahloune, May 23 2013
a(n) = 21*a(n-1)-154*a(n-2)+456*a(n-3)-448*a(n-4), for n >= 4. - Giovanni Resta, May 23 2013
|
|
MATHEMATICA
|
CoefficientList[Series[1/((1-2x)(1-4x)(1-7x)(1-8x)), {x, 0, 30}], x] (* Harvey P. Dale, Jun 23 2020 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|