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 A323339 #23 Feb 12 2024 07:57:53 %S A323339 1,1,3,7,11,347,3289,1011,38371,136553,4320019,12528587,40771123, %T A323339 29346499543,129990006917,1927874590951,903657004321,437445829053473, %U A323339 12456509813711881,187206004658210129,1974369484466728177,1967745662306280217,21401375717067880189 %N A323339 Numerator of the sum of inverse products of parts in all compositions of n. %C A323339 Numerators of the INVERT transform of reciprocal integers. %H A323339 Alois P. Heinz, <a href="/A323339/b323339.txt">Table of n, a(n) for n = 0..466</a> %F A323339 G.f. for fractions: 1 / (1 + log(1 - x)). - _Ilya Gutkovskiy_, Nov 12 2019 %F A323339 a(n) = numerator( A007840(n)/n! ). - _Alois P. Heinz_, Jan 04 2024 %F A323339 A323339(n)/A323340(n) ~ exp(n) / (exp(1) - 1)^(n+1). - _Vaclav Kotesovec_, Feb 12 2024 %e A323339 1/1, 1/1, 3/2, 7/3, 11/3, 347/60, 3289/360, 1011/70, 38371/1680, 136553/3780, 4320019/75600, 12528587/138600, 40771123/285120, ... = A323339/A323340 %p A323339 b:= proc(n) option remember; %p A323339 `if`(n=0, 1, add(b(n-j)/j, j=1..n)) %p A323339 end: %p A323339 a:= n-> numer(b(n)): %p A323339 seq(a(n), n=0..25); %t A323339 nmax = 20; Numerator[CoefficientList[Series[1/(1 + Log[1-x]), {x, 0, nmax}], x]] (* _Vaclav Kotesovec_, Feb 12 2024 *) %Y A323339 Denominators: A323340. %Y A323339 Cf. A000142, A007840, A011782, A088305, A177208, A177209, A322364, A322365, A322380, A322381, A323290, A323291. %K A323339 nonn,frac %O A323339 0,3 %A A323339 _Alois P. Heinz_, Jan 11 2019