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Revision History for A272766

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Showing entries 1-10 | older changes

A272766

Numbers n such that A281363(n) = n-1.
(history; published version)

#12 by N. J. A. Sloane at Fri Jan 27 19:07:05 EST 2017

STATUS

editing

approved

#11 by N. J. A. Sloane at Fri Jan 27 19:07:02 EST 2017

NAME

Numbers n such that A265163A281363(n) = n-1.

MATHEMATICA

Rest@ Union@ Table[If[# == n - 1, #, 0] &@ Block[{m = 1}, While[PowerMod[2^m, 2 n, 4 n^2 - 1] != 1, m++]; m], {n, 620}] + 1 (* Michael De Vlieger, May 06 2016, after Giovanni Resta at A265163 A281363 *)

CROSSREFS

Cf. A002110, A265163A281363.

STATUS

approved

editing

#10 by N. J. A. Sloane at Sun May 22 13:05:07 EDT 2016

STATUS

reviewed

approved

#9 by Danny Rorabaugh at Thu May 12 23:43:30 EDT 2016

STATUS

proposed

reviewed

#8 by Michael De Vlieger at Fri May 06 07:56:14 EDT 2016

STATUS

editing

proposed

#7 by Michael De Vlieger at Fri May 06 07:56:08 EDT 2016

MATHEMATICA

Table[SelectFirst[Range[10^5], PowerMod[2^#, 2 n, 4 n^2 - 1] == 1 &] /. k_ /; k != n - 1 -> Nothing, {n, 620}] + 1 (* Version 10.2, or *)

Rest@ Union@ Table[If[# == n - 1, #, 0] &@ Block[{m = 1}, While[PowerMod[2^m, 2 n, 4 n^2 - 1] != 1, m++]; m], {n, 620}] + 1 (* Michael De Vlieger, May 06 2016, after Giovanni Resta at A265163 *)

STATUS

proposed

editing

#6 by Michel Marcus at Fri May 06 04:24:44 EDT 2016

STATUS

editing

proposed

#5 by Michel Marcus at Fri May 06 04:24:31 EDT 2016

COMMENTS

Conjecture: primorial numbers (A002110) are the membres terms of a(n)this sequence.

STATUS

proposed

editing

#4 by Juri-Stepan Gerasimov at Fri May 06 03:30:15 EDT 2016

STATUS

editing

proposed

#3 by Juri-Stepan Gerasimov at Fri May 06 03:26:25 EDT 2016

COMMENTS

Conjecture: primorial numbers are the membres of a(n).

CROSSREFS

Cf. A002110, A265163.

KEYWORD

nonn,easy,changed