create function fn_fibo(@end int)
returns varchar(255)
as
begin
declare @a int, @b int,@fib int, @counter int
declare @fstring varchar(255) 
set @end = @end - 2
set @a = 0
set @b = 1
set @fib = 0
set @counter = 0
select @fstring = CAST(@a as varchar(10)) + ','
select @fstring = @fstring + CAST(@b as varchar(10))
while @counter < @end
begin
select @fstring = @fstring + ','
set @fib = @a + @b
set @a = @b
set @b = @fib
select @fstring = @fstring + CAST(@fib as varchar(20))
set @counter = @counter + 1 
end

create FUNCTION fn_fibo (@end INT)
RETURNS VARCHAR(255)
AS
BEGIN
	DECLARE @a INT
		,@b INT
		,@fib INT
		,@counter INT
	DECLARE @fstring VARCHAR(255)

	SET @end = @end - 2
	SET @a = 0
	SET @b = 1
	SET @fib = 0
	SET @counter = 0

	SELECT @fstring = CAST(@a AS VARCHAR(10)) + ','

	SELECT @fstring = @fstring + CAST(@b AS VARCHAR(10))

	WHILE @counter < @end
	BEGIN
		SELECT @fstring = @fstring + ','

		SET @fib = @a + @b
		SET @a = @b
		SET @b = @fib

		SELECT @fstring = @fstring + CAST(@fib AS VARCHAR(20))

		SET @counter = @counter + 1
	END

	RETURN @fstring
END

create FUNCTION itvf_fibo (@end INT)
RETURNS @FibNums table
(
	FibNum int
)
AS
BEGIN
	DECLARE @a INT
		,@b INT
		,@fib INT
		,@counter INT

	SET @end = @end - 2
	SET @a = 0
	SET @b = 1
	SET @fib = 0
	SET @counter = 0

	insert @FibNums
	select @a union all 
	select @b

	WHILE @counter < @end
	BEGIN
		SET @fib = @a + @b
		SET @a = @b
		SET @b = @fib
		insert @FibNums
		select @fib
		SET @counter = @counter + 1
	END
	return;
END

 CREATE FUNCTION dbo.FibNumber
        (@End INT)
RETURNS TABLE WITH SCHEMABINDING AS
 RETURN 
   WITH 
      R3(N) AS (SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1),
     R81(N) AS (SELECT 1 FROM R3 a, R3 b, R3 c, R3 d),
cteTally(N) AS (SELECT TOP (@End) ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM R81)
     SELECT t.N, 
            FibNumber = CAST((1/SQRT(5))*(POWER((1+SQRT(5))/2,t.N)-POWER((1-SQRT(5))/2,t.N)) AS BIGINT)
       FROM cteTally t
      WHERE 1 = CASE 
                WHEN @End BETWEEN 1 AND 70 
                THEN 1 
                ELSE 1/'[Error: Parameter of FibNumber greater than 70]' 
                END
;

 SELECT * FROM dbo.FibNumber(20);