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%I #23 Mar 18 2018 06:55:06
%S 1,12,360,1680,27720,1965600,116396280,758696400,18465927480,
%T 3962129371200,5637782470320,546077803471200,592841333318073840,
%U 717574218173821008000,66020319718147594800,111304867624125438463200
%N a(1) = 1; for n > 1, a(n) = LCM of next n composite numbers.
%C I.e., "next n composite numbers" following those that were used in computing a(n-1); see Example section. - _Jon E. Schoenfield_, Mar 18 2018
%H Robert Israel, <a href="/A074094/b074094.txt">Table of n, a(n) for n = 1..356</a>
%F for n >= 2, a(n) = lcm(A002808(A000217(n-1)...A000217(n)-1)). - _Robert Israel_, Jan 13 2016
%e a(2) = lcm(4,6) = 12;
%e a(3) = lcm(8,9,10) = 360;
%e a(4) = lcm(12,14,15,16) = 1680.
%p comps:= remove(isprime,[$2..10^4]):
%p N:= floor((sqrt(9+8*nops(comps))-1)/2):
%p 1, seq(ilcm(op(comps[(n-1)*n/2 .. n*(n+1)/2-1])), n=2..N); # _Robert Israel_, Jan 13 2016
%t Join[{1}, i = 3; Table[t = {}; c = 0; While[c != n, If[! PrimeQ[i], AppendTo[t, i]; c++]; i++]; LCM @@ t, {n, 2, 16}]] (* _Jayanta Basu_, Jul 30 2013 *)
%Y Cf. A000217, A002808.
%K nonn
%O 1,2
%A _Amarnath Murthy_, Aug 20 2002
%E More terms from _Sascha Kurz_, Jan 14 2003
%E Offset corrected by _Robert Israel_, Jan 13 2016
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