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%I #32 Oct 05 2020 10:56:38
%S 1,8,80,4374,9800,123200,336140,11859210,5142500,177182720,1611308699,
%T 3463199999,63927525375,421138799639,1109496723125,1453579866024,
%U 20628591204480,31887350832896,12820120234375,119089041053696,2286831727304144,9591468737351909375,17451620110781856,166055401586083680,49956990469100000,4108258965739505499,19316158377073923834000,386539843111191224
%N Largest number x such that x and x+1 are prime(n)-smooth but not prime(n-1)-smooth.
%C Note that this sequence is not always increasing. For many n, a(n) is the same as A002072(n). See A145605 for a triangle of values.
%C An effective abc conjecture (c < rad(abc)^2) would imply that a(29)-a(33) is (90550606380841216610, 205142063213188103639, 53234795127882729824, 4114304445616636016031, 124225935845233319439173). - _Lucas A. Brown_, Sep 20 2020
%H Jim White, <a href="https://11011110.github.io/blog/2007/03/23/smooth-pairs.html">Results to P = 127</a>
%Y Cf. A002072, A117581, A145605, A175607.
%K nonn,hard
%O 1,2
%A _T. D. Noe_, Oct 14 2008
%E Terms a(16) onward by _Andrey V. Kulsha_, Aug 10 2011, according to Jim White's computations
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