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%I #23 Sep 24 2018 08:49:24
%S 9,81,625,729,87808,14641,130321,6561,65536,59049,78125
%N a(n) is the least number c such that there are exactly n abc-hits with third member c, or 0 if no such c exists.
%C An abc-hit is a triple of coprime positive integers a, b, c such that a + b = c and rad(abc) < c, where rad(n) is the largest squarefree number dividing n.
%C Conjecture: a(n) > 0 for all n. - _Jianing Song_, Sep 21 2018
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Abc_conjecture">abc conjecture</a>
%e a(2) = 81 because there are exactly 2 abc-hits ((1, 80, 81) and (32, 49, 81)) with third member 81 and count of abc-hits with fixed third member c isn't equal to 2 for every c < 81.
%Y Cf. A272243.
%Y Cf. A120498, A130510 (possible values of c in abc-hits).
%Y Cf. A225426 (triples of abc-hits).
%Y Cf. A130512 (radicals of abc-hits).
%Y Cf. A007947 (radicals).
%K nonn,hard,more
%O 1,1
%A _Vladimir Letsko_, Apr 23 2016
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