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A049045 Domain of A049044. 4
1, 2, 4, 5, 7, 10, 11, 14, 17, 19, 22, 23, 31, 34, 37, 38, 41, 46, 61, 62, 71, 73, 74, 77, 82, 89, 103, 113, 122, 131, 139, 142, 146, 154, 157, 163, 167, 173, 178, 191, 193, 197, 206, 211, 226, 227, 233, 239, 251, 257, 262, 263, 278, 283, 293, 307, 313, 314, 317 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Positive integers that divide some positive element of A003422.

From Robert Israel, Nov 14 2016: (Start)

Numbers n such that A013584(n) > 0.

If n is in the sequence, then so are all divisors of n. (End)

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

filter:= proc(n) local t, r, m;

  r:= 1; t:= 1;

  for m from 1 do

    r:= r*m mod n;

    if r = 0 then return false fi;

    t:= t + r mod n;

    if t = 0 then return true fi;

  od;

end proc:

filter(1):= true:

select(filter, [$1..1000]); # Robert Israel, Nov 14 2016

MATHEMATICA

okQ[n_] := Module[{t, r, m}, r = 1; t = 1; For[m = 1, True, m++, r = Mod[r*m, n]; If[r == 0, Return[False]]; t = Mod[t + r, n]; If[t == 0, Return[True]]]];

okQ[1] = True;

Select[Range[1000], okQ] (* Jean-Fran├žois Alcover, Apr 10 2019, after Robert Israel *)

CROSSREFS

A049044, A003422, A013584.

Complement of A275608.

Sequence in context: A014370 A095278 A155722 * A153766 A319301 A093013

Adjacent sequences:  A049042 A049043 A049044 * A049046 A049047 A049048

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified March 31 03:48 EDT 2020. Contains 333136 sequences. (Running on oeis4.)