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A029569 Quasi-Carmichael numbers to base -9: squarefree composites n such that prime p|n ==> p+9|n+9. 2
231, 2679, 18471, 24311, 61171, 71799, 84271, 107371, 112871, 140151, 150071, 305359, 364791, 420391, 483351, 854845, 948631, 966671, 1003191, 1209745, 1260791, 1327911, 1451791, 1675511, 1691351, 1870167, 1982391, 2400935, 2721535 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..2185 (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[#, 9] &] (* Giovanni Resta, May 21 2013 *)

CROSSREFS

Sequence in context: A183664 A260302 A211717 * A152102 A183663 A201957

Adjacent sequences:  A029566 A029567 A029568 * A029570 A029571 A029572

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified February 27 11:38 EST 2021. Contains 341656 sequences. (Running on oeis4.)