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A183075 Numbers of the form 2^k - 1 for which each prime divisor has the form 4j + 3. 8
1, 3, 7, 31, 63, 127, 1023, 8191, 16383, 32767, 131071, 524287, 67108863, 1073741823, 2147483647, 17179869183, 274877906943, 8796093022207, 2251799813685247, 2305843009213693951 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
The Mersenne primes (A000668) are contained in this sequence.
Needed factorizations are in the Cunningham Project.
LINKS
S. S. Wagstaff, Jr., The Cunningham Project.
FORMULA
a(n) = 2^A183071(n) - 1.
EXAMPLE
63 = 2^6 - 1 = 3^2 * 7, and 3 and 7 have the form 4j + 3.
CROSSREFS
Sequence in context: A077315 A365423 A080168 * A292890 A042131 A109140
KEYWORD
nonn,hard
AUTHOR
Stuart Clary, Dec 23 2010
STATUS
approved

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Last modified May 26 20:29 EDT 2024. Contains 372844 sequences. (Running on oeis4.)