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 A272340 #15 Nov 03 2020 02:38:05
%S A272340 1,2,6,15,35,77,165,330,165,105,168,616,7777,13635,23760,3696,2079,
%T A272340 10395,5390,307230,15048,132264,1257510,395325,3083850,2384844,523740,
%U A272340 2797795,140270,25582260,19171284,5193078,1227303,124860330,183209730,267551691,388968349,51171505,14750505
%N A272340 First differences of 1/p(n), reciprocal of the number p(n) of unrestricted partitions of n (denominator).
%D A272340 Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 5.1 Abelian group enumeration constants, p. 274.
%H A272340 Amiram Eldar, <a href="/A272340/b272340.txt">Table of n, a(n) for n = 0..10000</a>
%F A272340 A272339(n) / a(n) = 1/p(n+1) - 1/p(n).
%t A272340 Table[1/PartitionsP[n], {n, 0, 60}] // Differences // Denominator
%o A272340 (PARI) a(n) = denominator(1/numbpart(n+1) - 1/numbpart(n)); \\ _Michel Marcus_, Nov 03 2020
%Y A272340 Cf. A000041, A272339 (numerators).
%K A272340 nonn,frac
%O A272340 0,2
%A A272340 _Jean-François Alcover_, Apr 26 2016