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Irregular triangle read by rows in which row n contains the first Carmichael number equal to m mod n where m is coprime to n, 0 <= m < n, ordered by m.
1

%I #9 Dec 12 2016 09:19:40

%S 561,561,1105,2465,561,8911,561,46657,52633,1729,1105,2465,561,46657,

%T 294409,29341,512461,1105,561,1024651,2821,8911,1729,1909001,2821,

%U 162401,1105,2465,561,52633,46657,1729,2465,1729,10585,29341,1105,46657,1193221

%N Irregular triangle read by rows in which row n contains the first Carmichael number equal to m mod n where m is coprime to n, 0 <= m < n, ordered by m.

%C The n-th row contains phi(n) terms. Wright proves that this sequence exists for each coprime m and n.

%H Charles R Greathouse IV, <a href="/A278338/b278338.txt">Rows n = 1..179 of triangle, flattened</a>

%H Thomas Wright, <a href="https://arxiv.org/abs/1212.5850">Infinitely many Carmichael numbers in arithmetic progressions</a>, Bulletin of the London Mathematical Society 45:5 (2013), pp. 943-952.

%F a(n) is the least Carmichael number equal to A038566(n) mod A038567(n).

%e 561 = 0 mod 1;

%e 561 = 1 mod 2;

%e 1105 = 1 mod 3, 2465 = 2 mod 3;

%e 561 = 1 mod 4, 8911 = 3 mod 4;

%e 561 = 1 mod 5, 46657 = 2 mod 5, 52633 = 3 mod 5, 1729 = 4 mod 5;

%e 1105 = 1 mod 6, 2465 = 5 mod 6;

%Y Cf. A002997, A038566, A038567.

%K nonn,tabf

%O 1,1

%A _Charles R Greathouse IV_, Nov 18 2016