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2022-04-20, 15:58   #540
chris2be8

Sep 2009

22×587 Posts

Quote:
 Originally Posted by Happy5214 Does Markus's script know to factor these large products algebraically first? That would be a huge help.
Quote:
 Hello Chris, looks like there are tons of numbers which are just the product of several expressions. I'll run a script for these now, might take a while. Markus
This will clear out a lot of junk. But probably produce a load of small entries for the various expressions that make up the junk. But at least some of them will be SNFS targets.

 2022-05-07, 14:45 #541 RichD     Sep 2008 Kansas 359810 Posts This really slows down work in the database. Attached Thumbnails
 2022-05-15, 14:14 #542 sweety439     "99(4^34019)99 palind" Nov 2016 (P^81993)SZ base 36 3,461 Posts There were many small composites < 10^18 (from a bug) in Oct 2021, and all of them had been deleted, but there were also many small primes < 10^18, also from the same bug, but why they have not been deleted? I think they also need to be deleted.
 2022-05-20, 14:19 #543 Happy5214     "Alexander" Nov 2008 The Alamo City 5·163 Posts Along with deleting those bad primes, please just delete/disable the modulo operator altogether if that hasn't been done already. It obviously isn't implemented correctly, it's not particularly useful, and tons of bogus data has resulted from its use.
2022-05-21, 07:34   #544
sweety439

"99(4^34019)99 palind"
Nov 2016
(P^81993)SZ base 36

3,461 Posts

Quote:
 Originally Posted by Happy5214 Along with deleting those bad primes, please just delete/disable the modulo operator altogether if that hasn't been done already. It obviously isn't implemented correctly, it's not particularly useful, and tons of bogus data has resulted from its use.
Not delete the modulo operator (%), but just fix this operator, also suggest lower case letters for variables, upper case letters for these functions: (delete these operators: "!!" = double factorial and "##" = product of first n primes, suggest to use "n!m" for the m-factorial function of n (multifactorial))

Code:
A      n! - (n-1)! + (n-2)! - ... 1!      A005165
B      Bell numbers      A000110
C      Catalan numbers      A000108
D      Distinct partition numbers      A000009
E      Euler zigzag numbers      A000111
F      Fermat numbers      A000215
G      Fubini numbers      A000670
H      H(m,n) = n-th m-Fibonacci numbers      A000045 A000129 A006190 A001076 ...
I      I(m,n) = n-th m-step Fibonacci numbers      A000045 A000073 A000078 A001591 ...
J      Coefficients of modular function j as power series in q = e^(2 Pi i t)      A000521
K      1! + 2! + 3! + ... + n!      A007489
L      L(m,n) = n-th m-Lucas numbers      A000032 A002203 A006497 A014448 ...
M      Mersenne numbers      A000225
N      N(m,n) = n!_(m) = m-factorial of n
O      O(m,n) = m-th cyclotomic polynomial evaluated at n
P      Partition numbers      A000041
Q      Perrin numbers      A001608
R      R(m,n) = repunit in base m with length n
S      S(m,n) = (Smarandache numbers) the concatenate the first n integers in base m
T      Ramanujan's tau function      A000594
U      U(n,p,q) = Lucas sequence U_n(p,q)
V      V(n,p,q) = Lucas sequence V_n(p,q)
W      W(m,n) = (Wolstenholme numbers) numerator of 1 + 1/(2^m) + 1/(3^m) + ... + 1/(n^m)
X      X(m,n) = (Smarandache-Wellin numbers) the concatenate the first n primes in base m
Y      Y(m,n) = n-th m-step Lucas numbers      A000032 A001644 A073817 A074048 ...
Z      Motzkin numbers      A001006
!      Factorial
#      Primorial
%      Modulo operator
\      Integer division
@      n@ = n-th prime
&      Narayana's cows sequence      A000930
\$      Padovan sequence      A000931

Last fiddled with by sweety439 on 2022-05-21 at 08:20

2022-05-22, 23:13   #545
sweety439

"99(4^34019)99 palind"
Nov 2016
(P^81993)SZ base 36

1101100001012 Posts

Quote:
 Originally Posted by Happy5214 Unless you're also immediately posting the Primo certs or doing P-1/P+1 proofs, please don't. Additions like those create extra work for the cert elves and are part of the overall problem.
P-1 and P+1 are "integer factoring" algorithm

N-1 and N+1 are "primality testing" algorithm

They are different (but I doubt whether they are related? After all, "integer factoring" algorithm also has ECM, and "primality testing" algorithm also has ECPP, and both of them uses elliptic curves, however, they are found by different people, P-1 is by Pollard, P+1 is by Williams, N-1 is by Pocklington, N+1 is by Morrison)

2022-05-22, 23:48   #546
Batalov

"Serge"
Mar 2008
Phi(4,2^7658614+1)/2

986210 Posts

Quote:
 Originally Posted by sweety439 wiki wiki They are different
The revenge of ...
Attached Thumbnails

2022-05-27, 12:04   #547
Happy5214

"Alexander"
Nov 2008
The Alamo City

5×163 Posts

Quote:
 Originally Posted by sweety439 P-1 and P+1 are "integer factoring" algorithm N-1 and N+1 are "primality testing" algorithm [,,,]
I was late for a meeting when I wrote that and didn't have time to proofread. I don't need the extended response.

Quote:
 Originally Posted by sweety439 Not delete the modulo operator (%), but just fix this operator [...]
Can you (or anyone) demonstrate any useful purpose for this operator that justifies its continued existence on this website, especially in the face of all the trouble it's caused? IMO all entries using it need to be purged.

 2022-05-27, 21:35 #548 Stargate38     "Daniel Jackson" May 2011 14285714285714285714 22·3·59 Posts I know of a reason to keep it. Since we don't have a built-in floor or ceiling function, we can represent it as floor(a/b)=(a-(a%b))/b, and ceil(a/b)=(a-(a%b))/b+1. We can use this to calculate floor(M521/10^100): http://www.factordb.com/index.php?id...00000824396765. That's far shorter than "(M521-4463459185543183397656052122559640661454554977296311391480858037121987999716643812574028291115057151)/10^100". Last fiddled with by Stargate38 on 2022-05-27 at 21:43
2022-05-28, 04:38   #549
sweety439

"99(4^34019)99 palind"
Nov 2016
(P^81993)SZ base 36

3,461 Posts

Quote:
 Originally Posted by Stargate38 I know of a reason to keep it. Since we don't have a built-in floor or ceiling function, we can represent it as floor(a/b)=(a-(a%b))/b, and ceil(a/b)=(a-(a%b))/b+1. We can use this to calculate floor(M521/10^100): http://www.factordb.com/index.php?id...00000824396765. That's far shorter than "(M521-4463459185543183397656052122559640661454554977296311391480858037121987999716643812574028291115057151)/10^100".
I suggest to add "\" (integer division)

Also, factordb has "n##" (product of the first n primes) but does not have "n@" (the n-th prime), I really do not know why, it is not reasonable! Thus I think that factordb should add "n@" for the n-th prime.

 2022-05-28, 15:02 #550 charybdis     Apr 2020 2ED16 Posts There is a common theme here: When people post here, nothing gets done. When people email Markus, he pays attention. It's pretty clear that Markus doesn't read this thread. In other words, for those who would like the modulo operator fixed/removed, I suggest dropping Markus an email. (Sweety: please don't spam him with lots of stupid suggestions. That might make him less willing to pay attention to serious suggestions.)

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