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 A000951 M3026 N1226 #21 May 19 2024 14:03:23
%S A000951 1,3,16,125,1296,16087,229384,3687609,66025360,1303751051,28151798544,
%T A000951 659841763957,16681231615816,452357366282655,13095632549137576,
%U A000951 403040561722348913,13138626717852194976,452179922268565180819,16381932383826669204640
%N A000951 Number of forests with n nodes and height at most 4.
%D A000951 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D A000951 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A000951 T. D. Noe, <a href="/A000951/b000951.txt">Table of n, a(n) for n = 1..100</a>
%H A000951 John Riordan, <a href="https://doi.org/10.1016/S0021-9800(68)80033-X">Forests of labeled trees</a>, J. Combin. Theory, 5 (1968), 90-103.
%F A000951 E.g.f.: exp(x*exp(x*exp(x*exp(x*exp(x))))).
%t A000951 nn = 20; Range[0, nn]! CoefficientList[Series[Exp[x*Exp[x*Exp[x*Exp[x*Exp[x]]]]], {x, 0, nn}], x] (* _T. D. Noe_, Jun 21 2012 *)
%Y A000951 Cf. A000248, A000949, A000950, A052512-A052514.
%Y A000951 Column k=4 of A210725. - _Alois P. Heinz_, Mar 15 2013
%K A000951 nonn
%O A000951 1,2
%A A000951 _N. J. A. Sloane_
%E A000951 More terms from _Vladeta Jovovic_, Apr 07 2001