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%I #3 Oct 01 2013 17:58:01
%S 3,7,17,52,207,999,5537,33753,220283,1513863,10833986,80107339,
%T 608461893,4726899406,37431060563,301327400284,2460711991071,
%U 20348626872625,170149288404678,1436870810843313
%N Integer part of the third nesting of the logarithmic integral of 10^n.
%F Let Li(n) = logarithmic integral of n. a(n) = Li(Li(Li(n)))
%o (PARI) \p 100 f(n) = for(x=1,n,print1(floor(Li(Li(Li(10^x))))",")) Li(x) = { -eint1(log(1/x)) }
%K nonn
%O 1,1
%A _Cino Hilliard_, Jun 30 2004