This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A275382 #14 Jul 27 2016 10:23:06 %S A275382 1,1,1,2,2,3,2,5,6 %N A275382 Number of odd prime factors (with multiplicity) of generalized Fermat number 11^(2^n) + 1. %F A275382 a(n) = A001222(A199592(n)) - 1 for n > 0. - _Felix Fröhlich_, Jul 25 2016 %e A275382 b(n) = (11^(2^n) + 1)/2. %e A275382 Complete Factorizations %e A275382 b(0) = 2*3 %e A275382 b(1) = 61 %e A275382 b(2) = 7321 %e A275382 b(3) = 17*6304673 %e A275382 b(4) = 51329*447600088289 %e A275382 b(5) = 193*257*21283620033217629539178799361 %e A275382 b(6) = 316955440822738177*P49 %e A275382 b(7) = 15361*111489577217*574341646346402207998363393* %e A275382 4018529583345312964042058778793458689*P55 %e A275382 b(8) = 15190529*4696846849*19618834249745000485889* %e A275382 4393553986026616439660661873903822389581313* %e A275382 290103547098489711747952055517085778590240759297*P138 %o A275382 (PARI) a001222(n) = bigomega(n) %o A275382 a199592(n) = 11^(2^n)+1 %o A275382 a(n) = if(n==0, 1, a001222(a199592(n))-1) \\ _Felix Fröhlich_, Jul 25 2016 %Y A275382 Cf. A199592, A273949. %K A275382 nonn,hard,more %O A275382 0,4 %A A275382 _Arkadiusz Wesolowski_, Jul 25 2016 %E A275382 a(8) was found in 2006 by Bruce Dodson