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A145099 a(n) = 1 if largest divisor of Mersenne composite A145097(n) is prime and a(n) = 0 in opposite case. 1
1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..38.

MATHEMATICA

a = {}; Do[m = 2^Prime[n] - 1; k = Divisors[m][[ -2]]; If[PrimeQ[m], null, If[PrimeQ[k], AppendTo[a, 1], AppendTo[a, 0]]], {n, 1, 50}]; a (* Artur Jasinski *)

CROSSREFS

Cf. A065341, A135975, A135980, A145097, A136031.

Sequence in context: A195198 A039966 A089451 * A070886 A041004 A141736

Adjacent sequences:  A145096 A145097 A145098 * A145100 A145101 A145102

KEYWORD

nonn

AUTHOR

Artur Jasinski, Oct 01 2008

STATUS

approved

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Last modified February 18 02:20 EST 2018. Contains 299297 sequences. (Running on oeis4.)