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Revision History for A124598

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Showing entries 1-10 | older changes
A124598
Primes p of the form k^2+s where k > 1 and 1 <= s < (k+1)^2, such that q = k^4+s is prime and larger than p.
(history; published version)
#35 by OEIS Server at Wed Apr 18 12:00:37 EDT 2018
LINKS

R. J. Cano, <a href="/A124598/b124598_1.txt">Table of n, a(n) for n = 1..10000</a>

#34 by Charles R Greathouse IV at Wed Apr 18 12:00:37 EDT 2018
STATUS

editing

approved

Discussion
Wed Apr 18
12:00
OEIS Server: Installed new b-file as b124598.txt.  Old b-file is now b124598_1.txt.
#33 by R. J. Cano at Wed Apr 18 11:59:08 EDT 2018
PROG

(PARI) findTerms(Pfinal)=my(k, t, L:list=List()); forprime(p=5, Pfinal, for(s=1, p, if(issquare(p-s, &k), if((k > 1) && ispseudoprime(t = (p-s)^2 + s), if((p<t) &&(s<(k+1)^2), listput(L, p); break))))); return(Vec(L)) \\ R. J. Cano, Apr 02 2018

#32 by Charles R Greathouse IV at Wed Apr 18 11:58:51 EDT 2018
PROG

(PARI) list(lim)=my(v=List(), k2, k4); lim\=1; for(k=2, sqrtint(lim-1), k2=k^2; k4=k2^2; forprime(p=k2+1, min(lim, 2*(k2+k)), if(isprime(k4+p-k2), listput(v, p)))); Set(v) \\ Charles R Greathouse IV, Apr 18 2018

KEYWORD

nonn,changed,easy

#31 by Charles R Greathouse IV at Wed Apr 18 11:53:46 EDT 2018
PROG

(PARI) {m=19; v=[]; for(k=2, m, for(s=1, (k+1)^2-1, if((p=k^2+s)<m^2&&isprime(p)&&(q=k^4+s)>p&&isprime(q), v=concat(v, p)))); print(Set(v))} \\ _Klaus Brockhaus_, Mar 05 2007

(PARI) findTerms(Pfinal)={my(k, t, L:list=List()); forprime(p=5, Pfinal, for(s=1, p, if(issquare(p-s, &k), if((k > 1) && ispseudoprime(t = (p-s)^2 + s), if((p<t) &&(s<(k+1)^2), listput(L, p); break))))); return(Vec(L))} \\ R. J. Cano, Apr 02 2018

(PARI) upto(n) = {my(res = List()); forprime(p = 5, n, for(k = ceil(sqrt(p / 2 + 1/4) - 0.5), sqrtint(p-1), if(isprime(k^4 + p - k^2), listput(res, p); next(2)))); res} \\ David A. Corneth, Apr 08 2018

(PARI) list(lim)=my(v=List(), k2, k4); lim\=1; for(k=2, sqrtint(lim-1), k2=k^2; k4=k2^2; forprime(p=k2+1, min(lim, 2*(k2+k)), if(isprime(k4+p-k2), listput(v, p)))); Set(v) \\ Charles R Greathouse IV, Apr 18 2018

STATUS

proposed

editing

Discussion
Wed Apr 18
11:56
R. J. Cano: Michel Marcus, Greetings!, I think already told you sir, with respect you deserve, I already told you clear and firmly I am working out that (Discussions length reduction from my part)  .
#30 by R. J. Cano at Wed Apr 18 11:23:30 EDT 2018
STATUS

editing

proposed

Discussion
Wed Apr 18
11:24
R. J. Cano: I don't care about others deletions on their own proposals... You're welcome.
11:36
Michel Marcus: Remy could you please write smaller discussions : right now they are 2 or 3 times as long as the OEIS entry itself.
11:50
R. J. Cano: With respect. Please remember always to click the button "Ready for review" unless you actually have something pending to do...
#29 by David A. Corneth at Tue Apr 17 13:27:40 EDT 2018
COMMENTS

Using R. J. Cano's code, the primes less than a million not in this sequence are 2, 3, 13, 19, 73, 103, 113, 131, 223, 293, 313, 461, 761, 863, 1013, 1069, 1171, 1223, 2293, 2711, 2887, 2903, 4583, 5623, 6949, 7151, 7873, 8563, 8803, 12413, 13613, 16703, 17393, 22013, 24733, 28723. - David A. Corneth, Apr 08 2018

Discussion
Tue Apr 17
13:28
David A. Corneth: I think by now complement is a sequence in OEIS
Wed Apr 18
11:23
R. J. Cano: Does something else still pending here?...
#28 by Michel Marcus at Tue Apr 17 13:19:23 EDT 2018
STATUS

proposed

editing

#27 by David A. Corneth at Sun Apr 08 15:50:56 EDT 2018
STATUS

editing

proposed

Discussion
Sun Apr 08
16:00
David A. Corneth: If p = k^2 + s and q = k^4 + s and k > 1 then q > p so that bit in the name isn't necessary right?
16:02
David A. Corneth: R. J. Cano, that sequence is now at A302485. P.s. I'd call you by your first name but I don't know it. If you don't mind, what is it?
21:54
R. J. Cano: Remy
22:01
R. J. Cano: please excuse me, I ignore the meaning of the short "HTH", for example I know "IMHO" "AFAIK" and "BTW", yet "RIFO" and "NOGI" (these last two frequent st OEIS's wiki, for instance). But never seen before (honestly) the "HTH", If you don't mind, what it means?, thanks.
22:04
R. J. Cano: Moreover, since English isn't my native language, please if someone of you know a source of those kind of shorts for English, please let me know it. Or perhaps... Should I google them as "acronyms"?... thanks.
22:45
R. J. Cano: Well, it isn't difficult: http://www.smart-words.org/abbreviations/text.html, if someone else also had my question in such matter.
Mon Apr 09
04:33
David A. Corneth: When I wonder what something means, I'd Google that frase with "meaning", for example, searching for "HTH meaning" gives what it means.
04:34
David A. Corneth: My native tongue is Dutch, I'm learning too, mostly by reading and writing, less by conversation in English
Tue Apr 17
13:19
Michel Marcus: yes I don't think we need new comment with sequence complement
#26 by David A. Corneth at Sun Apr 08 15:50:05 EDT 2018
PROG

(PARI) findTerms(Pfinal)={my(k, t, L:list=List()); forprime(p=5, Pfinal, for(s=1, p, if(issquare(p-s, &k), if((k > 1) && ispseudoprime(t = (p-s)^2 + s), if((p<t) &&(s<(k+1)^2), listput(L, p); break))))); return(Vec(L))} \\ R. J. Cano, Apr 02 2018

(PARI) upto(n) = {my(res = List()); forprime(p = 5, n, for(k = ceil(sqrt(p / 2 + 1/4) - 0.5), sqrtint(p-1), if(isprime(k^4 + p - k^2), listput(res, p); next(2)))); res} \\ David A. Corneth, Apr 08 2018

STATUS

proposed

editing

Discussion
Sun Apr 08
15:50
David A. Corneth: Sure, will do. I put a new prog as well. HTH.

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