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%I #13 Mar 14 2015 13:56:01
%S 2,6,30,61813313,206658174154973
%N a(n) = the smallest squarefree number (A005117) with n prime factors in a prime(m) + m progression.
%C Let p(m) = prime(m), let i(p(m)) = m, the subscript of p(m); a(n) = the smallest squarefree number with n prime factors of the form p_1 * p_2 * p_3 * ... * p_n, where p_1 < p_2 < p_3 < ... < p_n with p_n = p_(n-1) + i(p_(n-1)).
%C a(6) > 10^28.
%e 206658174154973 = 521*619*733*863*1013; 619 = 521 + 98, 733 = 619 + 114, 863 = 733 + 130, 1013 = 863 + 150 (521 = 98th prime, 619 = 114th prime, 733 = 130th prime, 863 = 150th prime).
%Y Cf. A000040, A005117, A232169, A232170.
%K nonn
%O 1,1
%A _Jaroslav Krizek_, Nov 19 2013
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