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 A033298 #22 Mar 19 2025 18:43:16
%S A033298 1,2,6,15,24,42,60,69,87,114,141,168,186,213,240,258,285,303,330,348,
%T A033298 357,384,411,438,465,483,510,519,546,573,600,609,636,663,699,726,753,
%U A033298 780,798,825,852,879,906,933,969,1005,1014,1041,1068,1086
%N A033298 a(n+1) = a(n) + sum of digits of a(n)^2, with a(1) = 1.
%H A033298 Harvey P. Dale, <a href="/A033298/b033298.txt">Table of n, a(n) for n = 1..1000</a>
%e A033298 a(6) = 42 as a(5) = 24 giving a(6) = 24 + (sum of digits of 24^2 = 576) = 24 + 5 + 7 + 6 = 42. - _David A. Corneth_, Jun 26 2022
%t A033298 NestList[#+Total[IntegerDigits[#^2]]&,1,50] (* _Harvey P. Dale_, Sep 21 2023 *)
%o A033298 (PARI) first(n) = {n=max(n,1); my(res=vector(n)); res[1] = 1; for(i = 2, n, res[i] = res[i-1] + sumdigits(res[i-1]^2)); res} \\ _David A. Corneth_, Jun 26 2022
%Y A033298 Cf. A047892, A004207, A007953.
%Y A033298 Partial sums of A139417.
%K A033298 nonn,base,easy,less
%O A033298 1,2
%A A033298 Miklos SZABO (mike(AT)ludens.elte.hu)