The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A049282 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A049282

Primes p such that both p-2 and p+2 are squarefree.
(history; published version)

#21 by Joerg Arndt at Sun Jun 26 06:27:28 EDT 2016

STATUS

reviewed

approved

#20 by Michel Marcus at Sun Jun 26 02:14:43 EDT 2016

STATUS

proposed

reviewed

#19 by Wesley Ivan Hurt at Sat Jun 25 21:42:20 EDT 2016

STATUS

editing

proposed

#18 by Wesley Ivan Hurt at Sat Jun 25 21:41:44 EDT 2016

MAPLE

with(numtheory): A049282:=n->`if`(isprime(n) and issqrfree(n-2) and issqrfree(n+2), n, NULL): seq(A049282(n), n=1..10^3); # Wesley Ivan Hurt, Jun 25 2016

MATHEMATICA

lst={}; Do[p=Prime[n]; If[SquareFreeQ[p-2]&&SquareFreeQ[p+2], AppendTo[lst, p]], {n, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Dec 20 2008 *)

STATUS

proposed

editing

#17 by Michel Marcus at Wed Jun 22 15:18:22 EDT 2016

STATUS

editing

proposed

#16 by Michel Marcus at Wed Jun 22 15:17:39 EDT 2016

PROG

(PARI) lista(nn) = forprime(p=2, nn, if (issquarefree(p-2) && issquarefree(p+2), print1(p, ", "))); \\ Michel Marcus, Jun 22 2016

STATUS

proposed

editing

#15 by John Cerkan at Wed Jun 22 13:27:18 EDT 2016

STATUS

editing

proposed

#14 by John Cerkan at Wed Jun 22 13:26:41 EDT 2016

LINKS

John Cerkan, <a href="/A049282/b049282.txt">Table of n, a(n) for n = 1..10000</a>

STATUS

approved

editing

#13 by Alois P. Heinz at Thu Jan 08 04:06:50 EST 2015

STATUS

proposed

approved

#12 by Michel Marcus at Thu Jan 08 00:49:42 EST 2015

STATUS

editing

proposed