A208156 8-Knödel numbers.

12, 14, 16, 20, 24, 32, 40, 48, 56, 60, 80, 88, 96, 104, 120, 136, 140, 152, 160, 184, 224, 232, 240, 248, 260, 296, 308, 328, 344, 376, 408, 416, 424, 472, 480, 488, 528, 536, 560, 568, 584, 632, 664, 680, 712, 728, 776, 808, 824, 856, 872, 904, 1016, 1040

Offset: 1

Author

Paolo P. Lava, Feb 24 2012

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000
• Eric Weisstein's World of Mathematics, Knödel Numbers

Crossrefs

Cf. A002997, A050990, A033553, A050992, A050993, A208154, A208155, A208157, A208158.

Programs

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(10000,8)

Mathematica

Select[Range[10, 2000, 2], Divisible[# - 8, CarmichaelLambda[#]]&] (* Jean-François Alcover, Mar 01 2018 *)