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%I #11 Mar 14 2019 20:54:46
%S 1,2,3,4,5,6,7,8,14,48
%N Numbers n such that n, n+1 and n+2 are highly composite numbers (2), i.e., all prime divisors <= 7 (A002473).
%C No more terms < 3*10^7. Probably no more terms. - _David Wasserman_, Feb 10 2005
%C No more terms < 2^180. - _Donovan Johnson_, Oct 10 2012
%C There are no further terms: see A003032 (and maybe A002072). - _Don Reble_, Mar 14 2019
%e 48 is a member as 48, 49 and 50 have all prime divisors <= 7.
%o (PARI) mx=2^180+2; v=vector(4607193); c=0; for(e1=0, 180, x1=2^e1; for(e2=0, 113, x2=x1*3^e2; if(x2>mx, next(2)); for(e3=0, 77, x3=x2*5^e3; if(x3>mx, next(2)); for(e4=0, 64, x4=x3*7^e4; if(x4>mx, next(2)); c++; v[c]=x4)))); v=vecsort(v); for(i=1, 4607191, if(v[i+1]-v[i]==1, if(v[i+2]-v[i]==2, print1(v[i] ", ")))) /* _Donovan Johnson_, Oct 10 2012 */
%Y Cf. A002473.
%K nonn,fini,full
%O 1,2
%A _Amarnath Murthy_, Jul 09 2003
%E Offset corrected and missing term added by _Donovan Johnson_, Oct 10 2012
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