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Composite numbers of the form 2^p - 1, with p prime, for which each prime divisor has the form 4j + 3.
8

%I #9 Feb 18 2019 06:10:50

%S 8796093022207,604462909807314587353087,

%T 12554203470773361527671578846415332832204710888928069025791,

%U 4171849679533027504677776769862406473833407270227837441302815640277772901915313574263597826047

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

%C Needed factorizations are in the Cunningham Project.

%H Amiram Eldar, <a href="/A183078/b183078.txt">Table of n, a(n) for n = 1..12</a>

%H S. S. Wagstaff, Jr., <a href="http://homes.cerias.purdue.edu/~ssw/cun/index.html">The Cunningham Project</a>.

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

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

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

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

%K nonn,hard

%O 1,1

%A _Stuart Clary_, Dec 23 2010