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%I #5 Jun 19 2016 19:52:22
%S 6075,23275,25856,26900,33524,45324,46475,61299,61347,77076,82075,
%T 93924,96236,107775,111924,117324,118700,133524,137924,155771,209524,
%U 210176,219275,229275,230643,234099,257724,258475,272924,275300,278271,312987,325899,332667,348524
%N Numbers n such that n and n+1 both have 18 divisors.
%H Charles R Greathouse IV, <a href="/A274360/b274360.txt">Table of n, a(n) for n = 1..10000</a>
%o (PARI) is(n)=numdiv(n)==18 && numdiv(n+1)==18
%o (PARI) list(lim)=my(v=List()); forprime(p=2,sqrtint(lim\12), forprime(q=2,sqrtint(lim\p^2\2), if(p==q,next); my(pq2=(p*q)^2); forprime(r=2,lim\pq2, if(p==r || q==r, next); t=pq2*r; if(numdiv(t-1)==18, listput(v,t-1)); if(numdiv(t+1)==18, listput(v,t))))); Set(v)
%Y Intersection of A005237 and A030636.
%Y Cf. A000005, A274357.
%K nonn
%O 1,1
%A _Charles R Greathouse IV_, Jun 19 2016