mersenneforum.org (https://www.mersenneforum.org/index.php)
-   cmd (https://www.mersenneforum.org/forumdisplay.php?f=139)
-   -   index of TF (https://www.mersenneforum.org/showthread.php?t=23514)

 cmd 2018-07-19 14:26

index of TF

__ 0 1 2 3 4

__ 0 2 4 6 8
05 | 01
15 | 03 <<== 2+1 ( 2+1 ) index 2

35 | 07
45 | 09 <<== 5+4 ( 03*03 ) index 5
-
55 | 11
65 | 13

85 | 17
95 | 19
__ 1 3 5 7 9

2z-1 == (z+1)/2

(_|\/|_)

 science_man_88 2018-07-19 14:44

[QUOTE=cmd;492121]
2z-1 == (z+1)/2
[/QUOTE]

z==1

 cmd 2018-07-19 15:01

[QUOTE=science_man_88;492123]z==1[/QUOTE]

I ... sm88

pari gp > if ( z == 49 , print ( " 97 is prime " ) )

 science_man_88 2018-07-19 15:12

[QUOTE=cmd;492124]I ... sm88

pari gp > if ( z == 49 , print ( " 97 is prime " ) )[/QUOTE]

congruence works in this case for divisors of 72 = (2*49-1)-((49+1)/2)=97-25

 cmd 2018-07-19 15:34

[QUOTE=science_man_88;492125]congruence works in this case for divisors of 72 = (2*49-1)-((49+1)/2)=97-25[/QUOTE]

25 is index of num 49 ( 25+24 ) 07 ( 4+3 ) 07^2 ( z=25) (z+=35) ndx 60 num 119 = 120-1
49 is ndx of num 97 ( 49+48 )

( z+=35 ) 95 ndx of num 189
( z+=35 ) 130 ndx of num 259
for ever ... continue

 cmd 2018-07-24 14:24

1 Attachment(s)
unique "grid" model

 cmd 2018-10-16 13:17

2 Attachment(s)
"group" H 11

group Y 21 ( sequence ) 43, 109, ... oo

(_|\/|_)

 cmd 2018-10-16 13:38

2 Attachment(s)
u see structure :

___ = 777

.._ = 778

replace line for prime

+ ( 776 )

 cmd 2019-11-21 16:21

5 Attachment(s)
5of10

 cmd 2019-11-25 13:13

[B]dec[/B]

0 0
1 9 x
2 8
3 7 +
4 6
5 5 *
6 4
7 3 +
8 2
9 1 x

[B] hex[/B]
0 0
1 f
2 e
3 d
4 c +
5 b
6 a *
7 9
8 8 *
9 7
a 6 *
b 5
c 4 +
d 3
e 2
f 1

(_|\/|_)

 All times are UTC. The time now is 19:34.