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Revision History for A279183

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Showing entries 1-10 | older changes

A279183

Numbers k such that phi(6k) = phi(6k-2), where phi is Euler's totient function A000010.
(history; published version)

#16 by Charles R Greathouse IV at Thu Sep 08 08:46:18 EDT 2022

PROG

(MAGMAMagma) [n: n in [1..2*10^6] | EulerPhi(6*n) eq EulerPhi(6*n-2)]; // Vincenzo Librandi, Dec 11 2016

Discussion

Thu Sep 08

08:46

OEIS Server: https://oeis.org/edit/global/2944

#15 by Michel Marcus at Sun Dec 11 02:49:33 EST 2016

STATUS

reviewed

approved

#14 by Joerg Arndt at Sun Dec 11 02:06:02 EST 2016

STATUS

proposed

reviewed

#13 by Michel Marcus at Sun Dec 11 01:54:25 EST 2016

STATUS

editing

proposed

#12 by Michel Marcus at Sun Dec 11 01:54:21 EST 2016

KEYWORD

nonn,more,new

#11 by Michel Marcus at Sun Dec 11 01:54:03 EST 2016

PROG

(PARI) isok(k) = eulerphi(6*k) == eulerphi(6*k-2); \\ Michel Marcus, Dec 11 2016

STATUS

proposed

editing

#10 by Vincenzo Librandi at Sun Dec 11 00:58:53 EST 2016

STATUS

editing

proposed

#9 by Vincenzo Librandi at Sun Dec 11 00:58:44 EST 2016

MATHEMATICA

a = {}; Do[If[EulerPhi[6k] == EulerPhi[6 k - 2], AppendTo[a, k]], {k, 1000000}]; a (* Vincenzo Librandi, Dec 11 2016 *)

#8 by Vincenzo Librandi at Sun Dec 11 00:47:41 EST 2016

DATA

1, 2, 12, 152, 222, 362, 432, 992, 1517, 2532, 2567, 8472, 34732, 44092, 69312, 82752, 105852, 114392, 128672, 336992, 350082, 393132, 393552, 462747, 497712, 559872, 665817, 714502, 931432, 968952, 1126602, 1281867, 1389337, 1449992, 1638712, 1694292

PROG

(MAGMA) [n: n in [1..2*10^6] | EulerPhi(6*n) eq EulerPhi(6*n-2)]; // Vincenzo Librandi, Dec 11 2016

EXTENSIONS

More terms from Vincenzo Librandi, Dec 11 2016

STATUS

approved

editing

#7 by N. J. A. Sloane at Sat Dec 10 20:44:00 EST 2016

STATUS

editing

approved