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A208158 10-Knödel numbers. 12
12, 24, 28, 30, 50, 70, 110, 130, 150, 170, 190, 230, 290, 310, 330, 370, 410, 430, 442, 470, 530, 532, 550, 590, 610, 670, 710, 730, 790, 830, 890, 910, 970, 1010, 1030, 1070, 1090, 1130, 1270, 1310, 1370, 1390, 1490, 1510, 1570, 1630, 1650, 1670, 1730, 1790 (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's World of Mathematics, 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, 10)

MATHEMATICA

Select[Range[12, 1790, 2], Divisible[# - 10, CarmichaelLambda[#]]&] (* Jean-François Alcover, Mar 01 2018 *)

CROSSREFS

Cf. A002997, A050990, A033553, A050992, A050993, A208154-A208157.

Sequence in context: A167994 A065303 A239673 * A108902 A126935 A333918

Adjacent sequences:  A208155 A208156 A208157 * A208159 A208160 A208161

KEYWORD

nonn

AUTHOR

Paolo P. Lava, Feb 24 2012

STATUS

approved

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Last modified October 27 15:21 EDT 2021. Contains 348287 sequences. (Running on oeis4.)