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 A363257 #22 Jan 09 2025 10:00:46 %S A363257 0,1,2,3,5,10,31,257,16642,69247363,1198799355237125, %T A363257 359279973529237254190922184970, %U A363257 32270524844792355518177347536627638351478874995525184567711 %N A363257 a(n) = floor( ((a(n-1) + 1) / 2)^2 ) + 1 for n >= 1, with a(0) = 0. %C A363257 Iterated application of A033638, with a shift. %H A363257 Andrew Howroyd, <a href="/A363257/b363257.txt">Table of n, a(n) for n = 0..16</a> %H A363257 A. V. Aho and N. J. A. Sloane, <a href="https://web.archive.org/web/2024*/https://www.fq.math.ca/Scanned/11-4/aho-a.pdf">Some doubly exponential sequences</a>, Fibonacci Quarterly, Vol. 11, No. 4 (1973), pp. 429-437. %H A363257 A. V. Aho and N. J. A. Sloane, <a href="/A000058/a000058.pdf">Some doubly exponential sequences</a>, Fibonacci Quarterly, Vol. 11, No. 4 (1973), pp. 429-437 (original plus references that F.Q. forgot to include - see last page!) %F A363257 a(n) = A033638(a(n-1)+1) for n > 0. %F A363257 log a(n) ~ C * 2^n for some constant C. %o A363257 (PARI) a(n) = if(n < 1, 0, floor( ((a(n-1) + 1) / 2)^2 ) + 1) \\ _Andrew Howroyd_, Jan 01 2024 %Y A363257 Cf. A003095, A006894, A014980, A033638. %K A363257 nonn %O A363257 0,3 %A A363257 _Harry Richman_, May 23 2023