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A225514 -10-Knödel numbers. 9
4, 6, 8, 10, 12, 14, 24, 26, 30, 50, 56, 102, 110, 150, 152, 182, 276, 330, 350, 494, 550, 650, 770, 962, 1190, 1230, 1430, 1550, 1650, 2550, 2870, 3050, 3410, 3752, 3770, 4510, 4550, 5270, 6150, 6650, 6710, 9230, 9350, 10010, 10850, 11526, 12710, 12950, 15950 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Extension of k-Knödel numbers to k negative, in this case equal to -10. Composite numbers n > 0 such that if 1 < a < n and gcd(n,a) = 1 then a^(n+10) = 1 mod n.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..1000

Eric Weisstein's World of Mathematics, Knödel Numbers

MAPLE

with(numtheory); ListA225514:=proc(q, k) local a, n, ok;

for n from 2 to q do if not isprime(n) then ok:=1; for a from 1 to n do

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

od; if ok=1 then print(n); fi; fi; od; end: ListA225514(10^6, -10);

MATHEMATICA

Select[Range[10000], CompositeQ[#] && Divisible[# + 10, CarmichaelLambda[#]] &] (* Amiram Eldar, Mar 28 2019 *)

CROSSREFS

Cf. A208728.

Cf. A225506, A225507, A225508, A225509, A225510, A225511, A225512, A225513.

Sequence in context: A064938 A050990 A289425 * A161546 A231571 A286043

Adjacent sequences:  A225511 A225512 A225513 * A225515 A225516 A225517

KEYWORD

nonn

AUTHOR

Paolo P. Lava, May 09 2013

EXTENSIONS

More terms from Amiram Eldar, Mar 28 2019

STATUS

approved

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Last modified July 29 09:41 EDT 2021. Contains 346344 sequences. (Running on oeis4.)