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A050990 2-Knödel numbers. 11
4, 6, 8, 10, 12, 14, 22, 24, 26, 30, 34, 38, 46, 56, 58, 62, 74, 82, 86, 94, 106, 118, 122, 132, 134, 142, 146, 158, 166, 178, 182, 194, 202, 206, 214, 218, 226, 254, 262, 274, 278, 298, 302, 314, 326, 334, 346, 358, 362, 382, 386, 394, 398, 422, 446, 454, 458 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..690

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(1000, 2) # Paolo P. Lava, Feb 24 2012

CROSSREFS

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

Sequence in context: A061344 A066664 A064938 * A225514 A161546 A231571

Adjacent sequences:  A050987 A050988 A050989 * A050991 A050992 A050993

KEYWORD

nonn

AUTHOR

Eric W. Weisstein

STATUS

approved

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Last modified May 29 05:38 EDT 2016. Contains 273488 sequences.