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A029562 Quasi-Carmichael numbers to base -2: squarefree composites n such that for every prime p that divides n, p+2 divides n+2. 4
598, 3913, 11590, 32578, 91078, 95170, 154843, 179998, 301273, 317623, 668743, 1742830, 1806673, 2486482, 2517226, 4543423, 5013853, 5237230, 6360523, 6704773, 7342162, 8810503, 10775833, 12858118, 16650478, 18183823, 19230433, 21381358 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Donovan Johnson and Giovanni Resta, Table of n, a(n) for n = 1..600 (terms < 10^12, first 200 terms from Donovan Johnson)

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[#, 2] &] (* Giovanni Resta, May 21 2013 *)

CROSSREFS

Sequence in context: A215195 A262252 A252265 * A273810 A095746 A135846

Adjacent sequences:  A029559 A029560 A029561 * A029563 A029564 A029565

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified September 19 16:46 EDT 2020. Contains 337178 sequences. (Running on oeis4.)