|
Search: id:A087405
|
|
| |
|
| 2, 2, 22, 98, 502, 2498, 12502, 62498, 312502, 1562498, 7812502, 39062498, 195312502, 976562498, 4882812502, 24414062498, 122070312502, 610351562498, 3051757812502, 15258789062498, 76293945312502, 381469726562498
(list; graph; listen)
|
|
|
OFFSET
|
0,1
|
|
|
FORMULA
|
G.f.: ((1-x)(2-4x))/(1-4x-5x^2). For n>0: a(n)=4*5^(n-1)+2(-1)^n
|
|
MATHEMATICA
|
CoefficientList[Series[((1 - x)(2 - 4x))/(1 - 4x - 5x^2), {x, 0, 25}], x]
|
|
CROSSREFS
|
Adjacent sequences: A087402 A087403 A087404 this_sequence A087406 A087407 A087408
Sequence in context: A143807 A118454 A118326 this_sequence A001012 A040082 A014358
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Mario Catalani (mario.catalani(AT)unito.it), Sep 01 2003
|
|
|
Search completed in 0.002 seconds
|
