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 A361669 #14 Apr 09 2023 17:56:51
%S A361669 1,1,1,2,3,22,3355531547
%N A361669 a(n) = floor of sinh(sinh(sinh(...(1)...))) with n iterations.
%C A361669 a(7) = ~2.67*10^1457288834.
%C A361669 sinh(x) = (e^x - e^-x)/2 is dominated by e^x as x tends to infinity, meaning that the sequence grows tetrationally.
%H A361669 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HyperbolicSine.html">Hyperbolic Sine</a>.
%e A361669 a(0) = 1,
%e A361669 a(1) = floor(sinh(1)) = floor(1.175...) = 1,
%e A361669 a(2) = floor(sinh(sinh(1))) = floor(1.465...) = 1,
%e A361669 a(3) = floor(sinh(sinh(sinh(1)))) = floor(2.048...) = 2,
%e A361669 a(4) = floor(sinh(sinh(sinh(sinh(1))))) = floor(3.812...) = 3,
%e A361669 a(5) = floor(sinh(sinh(sinh(sinh(sinh(1)))))) = floor(22.627...) = 22,
%e A361669 a(6) = floor(sinh(sinh(sinh(sinh(sinh(sinh(1))))))) = 3355531547.
%p A361669 a:= n-> floor(evalf((sinh@@n)(1), 45)):
%p A361669 seq(a(n), n=0..6); # _Alois P. Heinz_, Mar 20 2023
%t A361669 Table[Floor[Nest[Sinh[n],1,n]],{n,0,7}]
%Y A361669 Cf. A000471, A073742.
%K A361669 nonn,easy
%O A361669 0,4
%A A361669 _Sylvia Zevi Abrams_, Mar 20 2023