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A145097 a(n) = largest divisor of the Mersenne composite A065341(n). 2
89, 178481, 2304167, 616318177, 164511353, 20408568497, 59862819377, 1416003655831, 3203431780337, 761838257287, 10334355636337793, 21514198099633918969, 224958284260258499201, 57912614113275649087721 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Note that not all the largest divisors are primes.

Which divisors are prime? - see A145099. - Artur Jasinski, Oct 04 2008

LINKS

Table of n, a(n) for n=1..14.

MATHEMATICA

a = {}; Do[m = 2^Prime[n] - 1; If[PrimeQ[m], null, AppendTo[a, Divisors[m][[ -2]]]], {n, 1, 40}]; a (* Artur Jasinski *)

CROSSREFS

Cf. A065341, A135975, A135980, A136031.

Sequence in context: A089158 A145098 A136031 * A080051 A243316 A072314

Adjacent sequences:  A145094 A145095 A145096 * A145098 A145099 A145100

KEYWORD

nonn

AUTHOR

Artur Jasinski, Oct 01 2008

STATUS

approved

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Last modified December 7 13:07 EST 2016. Contains 278875 sequences.