You can check this out:
DECLARE @myTable as table (Indx int)
INSERT INTO @myTable VALUES
(1),(2),(3),(4),(5),(6),(7),(8),(9),(10)
SELECT
Indx
,SUM(myTable.Indx) OVER(ORDER BY myTable.Indx ASC ROWS BETWEEN UNBOUNDED PRECEDING and CURRENT ROW) -- + myTable.Indx
AS [Cummulative]
,SUM(myTable.Indx) OVER(ORDER BY myTable.Indx ASC ROWS BETWEEN UNBOUNDED PRECEDING and 2 PRECEDING)
+ SUM(myTable.Indx) OVER(ORDER BY myTable.Indx ASC ROWS BETWEEN UNBOUNDED PRECEDING and 1 PRECEDING)
AS [Fibonacci]
from @myTable myTable