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%I #5 Nov 07 2016 14:34:49
%S 24,304,127744,33501184,8589082624,
%T 10384593717069654320312270165377024,
%U 822752278660603021077484591278411581166520461101278617407586304,15177100720513508366558296147058741458142670970377727126573378340391656803557965824
%N Solutions to Mod[sigma(x),x]=12 of the form p*(p+13)/2 where p is a prime of form=2^j-13, of which j exponents are listed in A096818.
%C The relevant A084306 includes additional solution like 21, while A076496 contains solutions of 6k form too.
%H F. Firoozbakht, M. F. Hasler, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL13/Hasler/hasler2.html">Variations on Euclid's formula for Perfect Numbers</a>, JIS 13 (2010) #10.3.1.
%e 8th term is (2^136)*(-13+2^137) with 83 decimal digits; n=4: a[4]=(2^3)*(16-13)=24;
%Y Cf. A084306, A096518, A000203, A076496.
%K nonn
%O 1,1
%A _Labos Elemer_, Jul 13 2004