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The largest 3-Carmichael number that is divisible by the n-th odd prime.
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%I #13 Aug 09 2017 23:16:51

%S 561,10585,52633,561,530881,7207201,1024651,1615681,5444489,471905281,

%T 36765901,2489462641,564651361,958762729,17316001,178837201,

%U 1574601601,7991602081,597717121,962442001,4461725581,167385219121,43286923681,4523928001,5755495201

%N The largest 3-Carmichael number that is divisible by the n-th odd prime.

%C Beeger proved in 1950 that if p < q < r are primes such that p*q*r is a Carmichael number, then q < 2p^2 and r < p^3. Therefore there is a finite number of 3-Carmichael numbers which divisible by a given prime.

%C The terms were calculated using Pinch's tables of Carmichael numbers (see link below).

%D N. G. W. H. Beeger, "On composite numbers n for which a^n == 1 (mod n) for every a prime to n", Scripta Mathematica, Vol. 16 (1950), pp. 133-135.

%H R. G. E. Pinch, <a href="http://s369624816.websitehome.co.uk/rgep/carpsp.html">Tables relating to Carmichael numbers</a>.

%Y Cf. A065091 (odd primes), A087788 (3-Carmichael numbers), A141706.

%K nonn

%O 1,1

%A _Amiram Eldar_, Aug 03 2017