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%I #23 Sep 10 2014 12:17:19
%S 2,2,2,4058471,462807341
%N First of the least n primes that are also consecutive terms of A005117 (squarefree numbers).
%C a(6) > 10^11.
%C a(6) <= 10211143417747. - _Jens Kruse Andersen_, Sep 09 2014
%C If the k-tuple conjecture is true then a(n) always exists. Weak upper bounds are
%C a(7) <= 105629504093565907896809
%C a(8) <= 9921941384213872059341198331469403
%C a(9) <= 376847848512740851019714299079899219399
%C a(10) <= 32108207632017215023964871615662539298039357
%C - _Jens Kruse Andersen_, Sep 10 2014
%e Trivially, primes 2, 3, and 5 are consecutive squarefree numbers so a(1)-a(3) are each 2.
%e 4058471, 4058473, 4058477, and 4058479 are the least 4 primes that are also consecutive squarefree numbers (4058472 = 2^3*3*11*15373, 4058474 = 2*7^2*41413, 4058475 = 3*5^2*53*1021, 4058476 = 2^2*19*53401, and 4058478 = 2*3^3*17*4421) so a(4) = 4058471.
%Y Cf. A005117; a(3) is first term in A242621; a(4) is first term in A246470; a(5) is first term in A246548.
%K nonn,hard,more
%O 1,1
%A _Hans Havermann_, Aug 27 2014
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