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A208155 7-Knödel numbers. 7
15, 49, 91, 133, 217, 259, 301, 427, 469, 511, 553, 679, 721, 763, 889, 973, 1015, 1057, 1099, 1141, 1267, 1351, 1393, 1477, 1561, 1603, 1687, 1897, 1939, 1981, 2107, 2149, 2191, 2317, 2359, 2443, 2569, 2611, 2653, 2779, 2863, 2947, 3031, 3073, 3199, 3241, 3409 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

Eric Weisstein, Knödel Numbers.

MAPLE

with(numtheory);

knodel:= proc(i, k)

local a, n, ok;

for n from k+1 to i do

  ok:=1;

  for a from 1 to n do

     if gcd(a, n)=1 then  if (a^(n-k) mod n)<>1 then ok:=0; break; fi; fi;

  od;

  if ok=1 then print(n); fi;

od;

end:

knodel(10000, 7);

MATHEMATICA

(* First run program for A208154 to define knodelQ *) Select[Range[3500], knodelQ[#, 7] &] (* Alonso del Arte, Feb 24 2012 *)

CROSSREFS

Cf. A002997, A050990, A033553, A050992, A050993, A208154, A208156-A208158.

Sequence in context: A065906 A154060 A168305 * A228219 A272039 A241577

Adjacent sequences:  A208152 A208153 A208154 * A208156 A208157 A208158

KEYWORD

nonn

AUTHOR

Paolo P. Lava, Feb 24 2012

STATUS

approved

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Last modified December 7 00:16 EST 2019. Contains 329812 sequences. (Running on oeis4.)