A029557 Quasi-Carmichael numbers to base 6: squarefree composites n such that (n,2*3*5) = 1 and prime p|n ==> p-6|n-6.

13481, 484133, 554749, 618481, 3898571, 13810481, 17710811, 27754681, 68170091, 113268161, 132484891, 488476513, 562612331, 629962801, 944029141, 1759856741, 2024292991, 2406729331, 2491302281, 2740377481, 2781100471, 3089281663

Offset: 1

Author

David W. Wilson

Keywords

• nonn

Comments

If multiples of 2, 3 and 5 are not excluded, then terms like 6, 10, 14, 15, 21, 30, 35,... belong to the sequence. - Giovanni Resta, May 21 2013

Links

• Giovanni Resta, Table of n, a(n) for n = 1..113 (terms < 5*10^12)
• Index entries for sequences related to Carmichael numbers.

Programs

Mathematica

qcm[n_, d_] := Block[{p, e}, {p, e} = Transpose@FactorInteger@n; Length[p] > 1 && Max[e] == 1 && d < Min[p] && And @@ IntegerQ /@ ((n - d)/(p - d))]; Select[Range[10^6], qcm[#, 6] &] (* Giovanni Resta, May 21 2013 *)