quote:

---

Originally posted by SamC
Would someone post the answers to the toughies?

---

quote:

---

Originally posted by spirit1

ran the last one in OEIS... i mean come on... who outside of US could've known that....

---

quote:

---

Originally posted by spirit1

what's OEIS??
<EDIT>
Arnold no fair... now you've spoiled the fun
OEIS = The On-Line Encyclopedia of Integer Sequences
</EDIT>


well they do

last one is giving me trouble.
also can't figure out 59, 154, 605, 1111,

Go with the flow & have fun! Else fight the flow

---

quote:

---

59 (+95) = 154 (+451) = 605 (+ 506) = 1111

---

set nocount on

declare @MathTable	table (uid int identity (1,1), Number	dec(38,0), NumberText char(100))
declare @Count 		int,	@BaseNumber	dec(38,0), @LoopCount int

set	@BaseNumber = 196
set	@Count = 1
set 	@LoopCount = 100

insert into @MathTable (Number,NumberText)
select	@BaseNumber,cast(@BaseNumber as char(100))

select * from @MathTable

while	@Count < @Loopcount
	begin
	insert into @MathTable (Number,NumberText)
	select	Number+cast(reverse(NumberText) as dec(38,0)),
		cast	(Number+ (cast(reverse(NumberText) as dec(38,0)))
			as char(100))
	from	@MathTable where	Uid = @Count 
	set	@Count = @Count + 1
end

select 	uid,
	Number,
	case
		when NumberText = reverse(NumberText) then 'Is Palindrome'
		else ' NOT Palindrome'
	end as [Palindrome?]
from 	@MathTable order by Uid desc

uid         Number                                   NumberText                                                                                           
----------- ---------------------------------------- ---------------------------------------------------------------------------------------------------- 
1           196                                      196                                                                                                 

Server: Msg 8115, Level 16, State 2, Line 17
Arithmetic overflow error converting expression to data type numeric.
The statement has been terminated.
uid         Number                                   Palindrome?     
----------- ---------------------------------------- --------------- 
81          71233793175007298122189281057030833206    NOT Palindrome
80          16474800379447118011108106559729985745    NOT Palindrome
79          8787394689723559555548553279865047867     NOT Palindrome
78          1797953072701241777777132207161449896     NOT Palindrome
77          899477035806065888888571598630674898      NOT Palindrome
76          171869639709643252636224690693706727      NOT Palindrome
75          91385319354816681317562845302348408       NOT Palindrome
74          45747659181913285659330927106673654       NOT Palindrome
73          13258878097456662332665448018788423       NOT Palindrome
72          7178889593228875666877224058899706        NOT Palindrome
71          3589444802113893332894111974449853        NOT Palindrome
70          1326313072829535757534829271313622        NOT Palindrome
69          668656536414767878767414635656756         NOT Palindrome
68          159876958854887988978955775977805         NOT Palindrome
67          85383533877444544434477942439447          NOT Palindrome
66          17671139534403958504034349321776          NOT Palindrome
65          8836114272647029296571625205388           NOT Palindrome
64          1712373124704184482497411473217           NOT Palindrome
63          906182107397142240703710191608            NOT Palindrome
62          182280281681549295517528109327            NOT Palindrome
61          96640091285774647759309104658             NOT Palindrome
60          17786453745152322604573635887             NOT Palindrome
59          9442681822581660752291773438              NOT Palindrome
58          1758434620324786522027424867              NOT Palindrome
57          934217310162393261013712428               NOT Palindrome
56          175837936477498486373973857               NOT Palindrome
55          92918473189299188236491928                NOT Palindrome
54          17537224026299926194218357                NOT Palindrome
53          9264161958699957602603728                 NOT Palindrome
52          1751196640799987135692157                 NOT Palindrome
51          925153265399993573340628                  NOT Palindrome
50          175095833209091234750057                  NOT Palindrome
49          92502871604050616929528                   NOT Palindrome
48          18408442064004592449047                   NOT Palindrome
47          9749270977546801719568                    NOT Palindrome
46          1795298270686072793597                    NOT Palindrome
45          947154635293536341848                     NOT Palindrome
44          177104867844767940077                     NOT Palindrome
43          93507933867933969538                      NOT Palindrome
42          47248966933966985264                      NOT Palindrome
41          13305261530450734933                      NOT Palindrome
40          7197630720180367016                       NOT Palindrome
39          3603815405135183953                       NOT Palindrome
38          1317620482294916822                       NOT Palindrome
37          664304741147513356                        NOT Palindrome
36          159482241005228405                        NOT Palindrome
35          85191620502609247                         NOT Palindrome
34          17653692772973576                         NOT Palindrome
33          8827391431036288                          NOT Palindrome
32          4413700670963144                          NOT Palindrome
31          1400255515443103                          NOT Palindrome
30          755127757721546                           NOT Palindrome
29          159547977975595                           NOT Palindrome
28          84724043932847                            NOT Palindrome
27          17602285712176                            NOT Palindrome
26          8801197801088                             NOT Palindrome
25          1800098901007                             NOT Palindrome
24          900544455998                              NOT Palindrome
23          450822227944                              NOT Palindrome
22          130992928913                              NOT Palindrome
21          70446464506                               NOT Palindrome
20          16403234045                               NOT Palindrome
19          8746117567                                NOT Palindrome
18          1794102596                                NOT Palindrome
17          897100798                                 NOT Palindrome
16          454050344                                 NOT Palindrome
15          227574622                                 NOT Palindrome
14          111589511                                 NOT Palindrome
13          60744805                                  NOT Palindrome
12          35322452                                  NOT Palindrome
11          18211171                                  NOT Palindrome
10          10755470                                  NOT Palindrome
9           1067869                                   NOT Palindrome
8           187088                                    NOT Palindrome
7           94039                                     NOT Palindrome
6           52514                                     NOT Palindrome
5           13783                                     NOT Palindrome
4           7436                                      NOT Palindrome
3           1675                                      NOT Palindrome
2           887                                       NOT Palindrome
1           196                                       NOT Palindrome

private void button5_Click(object sender, EventArgs e)
{
ulong n = 196;

for (int i=0;i<10000000;i++)
{
	ulong nRev;
	ulong.TryParse(Reverse(n.ToString()), out nRev);
	if (nRev == n )
		txtResults.Text += n.ToString() + Environment.NewLine + Environment.NewLine;
	n = n + nRev;
}

txtResults.Text += "Done! " + Environment.NewLine + Environment.NewLine;

}

private string Reverse(string x)
{
	char[] c = x.ToCharArray(); /*convert to chararray*/ 
	int l = x.Length - 1;
	for (int i = 0; i < l; i++, l--)
	{
		c[i] ^= c[l];
		c[l] ^= c[i];
		c[i] ^= c[l];
	} 
	string s = new string(c);
	return s;
}

quote:

---

Originally posted by spirit1

well i tried with this ... still nothing

private void button5_Click(object sender, EventArgs e)
{
ulong n = 196;

for (int i=0;i<10000000;i++)
{
	ulong nRev;
	ulong.TryParse(Reverse(n.ToString()), out nRev);
	if (nRev == n )
		txtResults.Text += n.ToString() + Environment.NewLine + Environment.NewLine;
	n = n + nRev;
}

txtResults.Text += "Done! " + Environment.NewLine + Environment.NewLine;

}

private string Reverse(string x)
{
	char[] c = x.ToCharArray(); /*convert to chararray*/ 
	int l = x.Length - 1;
	for (int i = 0; i < l; i++, l--)
	{
		c[i] ^= c[l];
		c[l] ^= c[i];
		c[i] ^= c[l];
	} 
	string s = new string(c);
	return s;
}

Go with the flow & have fun! Else fight the flow

---

declare @s1 varchar(8000), @palindrome char(10)
set @s1 = '59'
--set @s1 = '196'

select @s1 as seednumber

-- loop and display...
while len(@s1) < 8000
begin
	select	@s1 = dbo.addLarge(@s1, reverse(@s1))
	if @s1 = reverse(@s1) or len(@s1)%100 = 0
	begin
		set @palindrome = case when @s1 = reverse(@s1) then 'PALINDROME' else 'LEN='+ltrim(len(@s1)) end
		raiserror('%s : %s',0,1,@palindrome,@s1) with nowait
	end
end


if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[addLarge]') and xtype in (N'FN', N'IF', N'TF'))
drop function [dbo].[addLarge]
GO


/*	adds 2 large integer strings 
	terribly slow algorithm though ...
*/
create function dbo.addLarge(@s1 varchar(7999), @s2 varchar(7999))
returns varchar(8000) as
begin
	declare @s3 varchar(8000)
		,@i int
		,@rem int
		,@result int
	select	@rem = 0
		,@s3 = ''
		,@s1 = case when len(@s1)<len(@s2) then replicate('0',len(@s2)-len(@s1)) + @s1 else @s1 end
		,@s2 = case when len(@s2)<len(@s1) then replicate('0',len(@s1)-len(@s2)) + @s2 else @s2 end
		,@i = len(@s1)
	
	while @i > 0
	begin
		select	@result = @rem + cast(substring(@s1,@i,1) as int) + cast(substring(@s2,@i,1) as int)
			,@s3 = ltrim(@result%10) + @s3
			,@rem = @result/10
			,@i = @i - 1
	end
	
	return case when @rem = 0 then '' else ltrim(@rem) end + @s3
end
go