A029564 Quasi-Carmichael numbers to base -4: squarefree composites n such that prime p|n ==> p+4|n+4.

1886, 50711, 149171, 222101, 628421, 766931, 1105646, 1778621, 2523902, 5430047, 5836181, 6265805, 9306986, 10671881, 12450371, 21817715, 24953666, 32029934, 34836791, 38697746, 48807671, 55252571, 57264161, 63697721, 69300086, 74157926

Offset: 1

Author

David W. Wilson

Keywords

• nonn

Links

• Giovanni Resta, Table of n, a(n) for n = 1..541 (terms < 10^12)
• Index entries for sequences related to Carmichael numbers.

Programs

Mathematica

qcp[n_, d_] := Block[{p, e}, {p, e} = Transpose@FactorInteger@n;
Length[p] > 1 && Max[e] == 1 && And @@ IntegerQ /@ ((n + d)/(p + d))]; Select[Range[10^6], qcp[#, 4] &] (* Giovanni Resta, May 21 2013 *)