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A208155
7-Knödel numbers.
8
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
OFFSET
1,1
LINKS
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 *)
KEYWORD
nonn
AUTHOR
Paolo P. Lava, Feb 24 2012
STATUS
approved