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%I #26 May 28 2018 10:09:24
%S 2,3,7,13,61,421,841,2521,27721,360361,720721,12252241,232792561,
%T 5354228881,26771144401,80313433201,2329089562801,72201776446801,
%U 144403552893601,5342931457063201,219060189739591201
%N a(n) = 1 + lcm(1..k) where k is the n-th prime power A000961(n).
%C From _Daniel Forgues_, Apr 27 2014: (Start)
%C Factorizations:
%C 2, 3, 7, 13, 61, 421 are primes;
%C 841 = 29^2;
%C 2521 is prime;
%C 27721 = 19*1459, 360361 = 89*4049, 720721 = 71*10151,
%C 12252241 = 1693*7237;
%C 232792561 is prime;
%C 5354228881 = 6659*804059;
%C 26771144401 is prime;
%C 80313433201 = 331*11239*21589, 2329089562801 = 101*271*2311*36821;
%C 72201776446801 is prime.
%C Very likely contains an infinite number of primes (see A049536). (End)
%o (PARI) print1(2);t=1;for(n=2,100,if(t%n, t=lcm(t,n); print1(", "t+1))) \\ _Charles R Greathouse IV_, Jan 04 2013
%Y 1 + A003418(A000961(n)), corresponds to distinct values of 1 + A003418.
%Y Cf. A049536, A049537, A051454, A208768.
%K nonn
%O 1,1
%A _Labos Elemer_
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