cp's OEIS Frontend

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.

A007672 a(n) = A002034(n)!/n.

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%I A007672 M1669 #21 May 09 2017 10:41:24
%S A007672 1,1,2,6,24,1,720,3,80,12,3628800,2,479001600,360,8,45,20922789888000,
%T A007672 40,6402373705728000,6,240,1814400,1124000727777607680000,1,145152,
%U A007672 239500800,13440,180,304888344611713860501504000000
%N A007672 a(n) = A002034(n)!/n.
%D A007672 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A007672 A. J. Kempner, <a href="http://www.jstor.org/stable/2972639">Miscellanea</a>, Amer. Math. Monthly, 25 (1918), 201-210 [ See Section II, "Concerning the smallest integer m! divisible by a given integer n". ]
%t A007672 a[n_] := Module[{m = 1, x = n, as = 1, p}, While[x > 1, m++; p = GCD[x, m]; x = x/p; as *= m/p]; as]; Array[a, 30] (* _Jean-François Alcover_, May 09 2017, after _Antonio Roldán_ *)
%o A007672 (PARI) a(n)={local(m=1,x=n,as=1,p);while(x>1,m++;p=gcd(x,m);x=x/p;as*=m/p);as} \\ _Antonio Roldán_, Apr 04 2015
%K A007672 nonn,nice
%O A007672 1,3
%A A007672 _N. J. A. Sloane_, _Robert G. Wilson v_