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%I #6 Mar 30 2012 18:36:04
%S 79600343456925208350554324952070658488321,
%T 67727051825754224132985695308485992267126791150081,
%U 17096333467784942360991864487916588941402614691799041
%N CRF(13): consecutive refactorable numbers (rf, rf-1 are refactorable) such that 13 is the smallest prime divisor of rf.
%C The sequence has prime factorization (13*197)^12, (13*1093)^12, (13*1733)^12, (13*17*139)^12, (13*7877)^12, (13*16069)^12.
%F a(n) = is the n-th number rf such that both rf and rf-1 are refactorable and 13 is the smallest prime divisor of rf.
%e a(1)=(13*197)^12 is the first number rf such that rf refactorable, 13 is the smallest prime of rf and rf-1 is refactorable.
%Y Cf. A033950, A036898, A114617.
%K nonn,bref
%O 1,1
%A _Walter Kehowski_, Jun 22 2006
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