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A183078 Composite numbers of the form 2^p - 1, with p prime, for which each prime divisor has the form 4j + 3. 7
8796093022207, 604462909807314587353087, 12554203470773361527671578846415332832204710888928069025791, 4171849679533027504677776769862406473833407270227837441302815640277772901915313574263597826047 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Needed factorizations are in the Cunningham Project.

LINKS

Table of n, a(n) for n=1..4.

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

FORMULA

a(n) = 2^A183074(n) - 1.

EXAMPLE

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

CROSSREFS

Cf. A000668, A136005, A183075, A183076, A183077.

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

Sequence in context: A058124 A282540 A015436 * A057074 A017412 A017532

Adjacent sequences:  A183075 A183076 A183077 * A183079 A183080 A183081

KEYWORD

nonn,hard

AUTHOR

Stuart Clary, Dec 23 2010

STATUS

approved

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Last modified February 16 19:29 EST 2019. Contains 320167 sequences. (Running on oeis4.)