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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. 8
 8796093022207, 604462909807314587353087, 12554203470773361527671578846415332832204710888928069025791, 4171849679533027504677776769862406473833407270227837441302815640277772901915313574263597826047 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Needed factorizations are in the Cunningham Project. LINKS Amiram Eldar, Table of n, a(n) for n = 1..12 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 August 12 03:34 EDT 2020. Contains 336436 sequences. (Running on oeis4.)