A183077 - OEIS

A183077

Numbers of the form 2^p - 1, with p prime, for which each prime divisor has the form 4j + 3.

3, 7, 31, 127, 8191, 131071, 524287, 2147483647, 8796093022207, 2305843009213693951, 604462909807314587353087, 618970019642690137449562111, 162259276829213363391578010288127, 170141183460469231731687303715884105727

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OFFSET

1,1

COMMENTS

The Mersenne primes (A000668) are contained in this sequence.

Needed factorizations are in the Cunningham Project.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..26

S. S. Wagstaff, Jr., The Cunningham Project.

FORMULA

a(n) = 2^A183073(n) - 1.

EXAMPLE

8796093022207 = 2^43 - 1 = 431 * 9719 * 2099863.

CROSSREFS

Cf. A000668, A136005, A183075, A183076, A183078.

Cf. A000043, A136003, A183071, A183072, A183073, A183074.

Sequence in context: A057612 A136005 A336720 * A088552 A000668 A136007

Adjacent sequences: A183074 A183075 A183076 * A183078 A183079 A183080

KEYWORD

nonn,hard

AUTHOR

Stuart Clary, Dec 23 2010

STATUS

approved