A140769 Numbers n such that consecutive Mersenne numbers A000225(n-1) = M(n-1) = 2^(n-1) - 1 and A000225(n) = M(n) = 2^n - 1 are both squarefree.

2, 3, 4, 5, 8, 9, 10, 11, 14, 15, 16, 17, 23, 26, 27, 28, 29, 32, 33, 34, 35, 38, 39, 44, 45, 46, 47, 50, 51, 52, 53, 56, 57, 58, 59, 62, 65, 68, 69, 70, 71, 74, 75, 76, 77, 82, 83, 86, 87, 88, 89, 92, 93, 94, 95, 98, 99, 104, 107, 112, 113, 116, 117, 118, 119, 122, 123, 124

Offset

1,1

References

J.-M. De Koninck, Ces nombres qui nous fascinent, Footnote pp 18, Ellipses, Paris 2008.

Links

Amiram Eldar, Table of n, a(n) for n = 1..629

Crossrefs

Cf. A000225, A005117.

Sequence in context: A276878 A047247 A169606 * A364380 A352337 A032877

Adjacent sequences: A140766 A140767 A140768 * A140770 A140771 A140772

Keyword

nonn

Author

Lekraj Beedassy, Jul 13 2008

Status

approved