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 A239937 #21 Jul 03 2021 04:20:34
%S A239937 3,7,8,9,14,17,19,24,26,28,29,31,33,34,37,38,39,43,44,47,48,53,54,57,
%T A239937 59,63,64,67,69,70,74,77,78,79,83,84,87,88,89,93,94,97,98,99,104,107,
%U A239937 109,114,117,118,119,122,124,126,128,129,133,134,137,138,141,143
%N A239937 Numbers k such that DigitSum(k^2) > DigitSum((k+1)^2).
%e A239937 For k=3, we have DigitSum(3^2) = 9 > 7 = DigitSum(4^2).
%t A239937 lis = Table[Total[IntegerDigits[n^2, 10]], {n, 1, 100}];
%t A239937 Flatten[Position[Greater @@@ Partition[lis, 2, 1], True]]
%t A239937 Position[Partition[Total[IntegerDigits[#]]&/@(Range[150]^2),2,1],_?(#[[1]]> #[[2]]&),1,Heads->False]//Flatten (* _Harvey P. Dale_, Feb 19 2020 *)
%o A239937 (PARI) isok(k) = sumdigits(k^2) > sumdigits((k+1)^2); \\ _Michel Marcus_, Jul 03 2021
%Y A239937 Cf. A007953 (sum of digits of n), A004159 (sum of digits of n^2).
%K A239937 nonn,base
%O A239937 1,1
%A A239937 _Oliver Bel_, Mar 29 2014
%E A239937 More terms from _Jon E. Schoenfield_, Mar 29 2014