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A029564 Quasi-Carmichael numbers to base -4: squarefree composites n such that prime p|n ==> p+4|n+4. 3
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..541 (terms < 10^12)

Index entries for sequences related to Carmichael numbers.

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 *)

CROSSREFS

Sequence in context: A338705 A236613 A190133 * A235295 A237540 A206746

Adjacent sequences:  A029561 A029562 A029563 * A029565 A029566 A029567

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified November 30 08:19 EST 2021. Contains 349419 sequences. (Running on oeis4.)