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 A138113 #15 Mar 17 2022 01:05:25
%S A138113 1,2,6,24,120,720,5040,27720,166320,1441440,7207200,73513440,
%T A138113 367567200,4655851200,64250746560,1028011944960,5140059724800,
%U A138113 32607253879200,260858031033600,4620913692595200,97039187544499200,897612484786617600,9873737332652793600
%N A138113 a(n) is the smallest number with same number of divisors as n*a(n-1).
%F A138113 a(n) = A140635(n*a(n-1)). - _J. Lowell_, May 20 2008
%e A138113 For n=8, n*a(n-1) = 8*5040 = 40320 has 96 divisors, but the smallest number with 96 divisors is 27720, so a(8)=27720.
%o A138113 (PARI) A138113(n)={ local(an1,t) ; if(n<=2, return(n) ) ; an1 = A138113(n-1) ; t=length(divisors(n*an1)) ; return(A005179(t)) ; } {for (n=1,40, print1(A138113(n)", ") ; ) } \\ _R. J. Mathar_, Mar 20 2010
%Y A138113 Cf. A019505 (2*a(n-1)).
%Y A138113 Cf. A140635.
%K A138113 nonn
%O A138113 1,2
%A A138113 _J. Lowell_, May 04 2008
%E A138113 More terms from _R. J. Mathar_, Mar 20 2010
%E A138113 a(23) from _Jon E. Schoenfield_, Mar 17 2022