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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. 2
13481, 484133, 554749, 618481, 3898571, 13810481, 17710811, 27754681, 68170091, 113268161, 132484891, 488476513, 562612331, 629962801, 944029141, 1759856741, 2024292991, 2406729331, 2491302281, 2740377481, 2781100471, 3089281663 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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.

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 *)

CROSSREFS

Sequence in context: A250616 A115925 A234493 * A115922 A248444 A257149

Adjacent sequences:  A029554 A029555 A029556 * A029558 A029559 A029560

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified January 18 13:49 EST 2020. Contains 331010 sequences. (Running on oeis4.)