This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A113511 #14 Nov 21 2013 12:48:46
%S A113511 1,2,30,30030,6469693230,614889782588491410,
%T A113511 40729680599249024150621323470,
%U A113511 2566376117594999414479597815340071648394470,225319534991831177328890236228992001350685163362356544091910
%N A113511 Product of first A000217(n) = n(n+1)/2 primes.
%C A113511 a(n) is the smallest squarefree product of a prime, 2-almost prime (semiprime), 3-almost prime, ..., n-almost prime. The analogous sequence without the squarefree condition is A006125(n), n>=2: 2,8,64,1024,32768,....
%C A113511 Cumulative product of A007467. - _Franklin T. Adams-Watters_, Mar 17 2007
%H A113511 <a href="/index/Di#divseq">Index to divisibility sequences</a>
%F A113511 a(n) = prod(k=1, n*(n+1)/2, prime(k)).
%F A113511 a(n) = A002110(A000217(n)). - _Franklin T. Adams-Watters_, Mar 17 2007
%F A113511 log a(n) ~ n^2 log n. [_Charles R Greathouse IV_, Jan 13 2012]
%e A113511 a(4) = 2*(3*5)*(7*11*13)*(17*19*23*29) = 6469693230, the product of the first A000217(4) = 4*5/2 = 10 primes. 6469693230 = 2*15*1001*215441, where 2 is prime, 15 is 2-almost prime, 1001 is 3-almost prime and 215441 is 4-almost prime.
%e A113511 (Of course if the prime factors are rearranged, other primes and almost primes in the same pattern give this same product.)
%t A113511 nn=10;With[{prs=Prime[Range[(nn(nn+1))/2]]},Table[Times@@Take[prs,(n(n+1))/2], {n,0,nn}]] (* _Harvey P. Dale_, Sep 13 2011 *)
%o A113511 (PARI) a(n)=my(v=primes(n*(n+1)/2));prod(i=1,#v,v[i]) \\ _Charles R Greathouse IV_, Jan 13 2012
%Y A113511 Cf. A000217 (triangular numbers), A006125 (2^{n(n-1)/2}).
%Y A113511 Cf. A002110, A007467.
%K A113511 nonn
%O A113511 0,2
%A A113511 _Rick L. Shepherd_, Jan 11 2006