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A135386 Mersenne composites A065341 with 4 or more prime factors. 1
10384593717069655257060992658440191, 2854495385411919762116571938898990272765493247, 182687704666362864775460604089535377456991567871 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..3.

MAPLE

A135386 := proc(n) local i;

i := 2^(ithprime(n))-1:

if (nops(numtheory[factorset](i)) > 3) then

   RETURN (i)

fi: end: seq(A135386(n), n=1..37); # Jani Melik, Feb 09 2011

MATHEMATICA

k = {}; Do[If[ ! PrimeQ[2^Prime[n] - 1], c = FactorInteger[2^Prime[n] - 1]; d = Length[c]; If[d >3, AppendTo[k, 2^Prime[n] - 1]]], {n, 1, 40}]; k

CROSSREFS

Subsequence of A065341.

Cf. A000225, A054723, A134852, A135975, A135976, A135977, A135979.

Sequence in context: A083103 A115532 A074194 * A095462 A115543 A219323

Adjacent sequences:  A135383 A135384 A135385 * A135387 A135388 A135389

KEYWORD

nonn,bref

AUTHOR

Artur Jasinski, Dec 09 2007

STATUS

approved

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Last modified November 21 12:20 EST 2019. Contains 329370 sequences. (Running on oeis4.)