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%I #14 Nov 24 2013 15:13:46
%S 6,15,77,247,4819,7979,10057,12827,21353,24047,40363,60433,121411,
%T 146231,154729,211763,273509,301297,322499,346781,367063,382937,
%U 394091,415693,453727,485237,579727,632579,803017,874219,910073,1009823,1218053,1335181,1740329
%N Squarefree numbers (A005117) of form prime(k)*q where q = primes of the form prime(k) + k.
%C Let p(m) = prime(m), let i(p(m)) = m, the subscript of p(m); a(n) = squarefree numbers with 2 prime factors of the form p_1 * p_2 where p_1 < p_2 with p_2 = p_1 + i(p_1).
%C Subsequence of A232169.
%H Jaroslav Krizek, <a href="/A232170/b232170.txt">Table of n, a(n) for n = 1..900</a>
%e Number 10057 = 89 * 113 is in sequence because 89 = prime(24) and 113 = 89 + 24.
%Y Cf. A000040, A005117, A232169, A232171.
%K nonn
%O 1,1
%A _Jaroslav Krizek_, Nov 19 2013