TSQL generation sequence, date sequence

--Method 1SETNOCOUNT on UsetempdbGOIF object_id('dbo.nums') is  not NULLDROP TABLEdbo.nums;GOCREATE TABLEDbo.nums (nINT  not NULL PRIMARY KEY);DECLARE @max  as INT,@rc  as INTSET @max=1000000SET @rc=1INSERT  intoNumsVALUES(1); while @rc*2<=@maxBEGIN    INSERT  intoNumsSELECTN+@rc  fromNums; SET @rc=@rc*2END--SELECT [email protected] from nums WHERE [email protected]<[email protected]GODECLARE @s  as DATETIME,@e  as DATETIMESET @s='20140501'SET @e='20141231'SELECT @s+N-1  asDt fromNumsWHEREN<=DATEDIFF( Day,@s,@e)+1SELECT *  fromNumsWHEREN<TenGO--Method 2IF object_id('fn_nums') is  not NULLBEGIN     PRINT 'dropping function Fn_nums'    DROP FUNCTIONfn_numsIF @ @ERROR = 0 PRINT 'Function Fn_nums dropped'ENDGoCREATE FUNCTIONFn_nums (@n  as BIGINT) RETURNS TABLE     as RETURN withL0 as(SELECT 1  asCUNION  All SELECT 1), L1 as(SELECT 1  asC fromL0 asA,l0 asb), L2 as(SELECT 1  asC fromL1 asA,l1 asb), L3 as(SELECT 1  asC fromL2 asA,l2 asb), L4 as(SELECT 1  asC fromL3 asA,l3 asb), L5 as(SELECT 1  asC fromL4 asA,l4 asb), Nums as(SELECTRow_number () Over(ORDER  byC asN fromL5)SELECTN fromNumsWHEREN<=@nGODECLARE @s  as DATETIME,@e  as DATETIMESET @s='20140501'SET @e='20141231'SELECT @s+N-1  asDt fromDbo.fn_nums (DATEDIFF( Day,@s,@e)) asnums;SELECT *  fromDbo.fn_nums (Ten)