A145099 a(n) = 1 if the largest proper divisor of Mersenne composite A145097(n) is prime and a(n) = 0 in opposite case.

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, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..191

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

Crossrefs

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

Sequence in context: A195198 A039966 A089451 * A374045 A205083 A070886

Adjacent sequences: A145096 A145097 A145098 * A145100 A145101 A145102

Keyword

nonn

Author

Artur Jasinski, Oct 01 2008

Extensions

Name clarified and more terms added by Amiram Eldar, Mar 12 2020

Status

approved