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 A231503 #14 Jan 20 2022 10:31:03
%S A231503 0,1,5,6,10,19,23,32,48,49,53,62,66,75,91,100,116,141,145,154,170,179,
%T A231503 195,220,236,261,297,298,302,311,315,324,340,349,365,390,394,403,419,
%U A231503 428,444,469,485,510,546,555,571,596,612,637,673,698,734,783,787,796,812,821,837,862,878,903,939,948,964,989,1005,1030,1066,1091,1127,1176,1192,1217,1253,1278
%N A231503 a(n) = Sum_{i=0..n} digsum_3(i)^2, where digsum_3(i) = A053735(i).
%H A231503 Amiram Eldar, <a href="/A231503/b231503.txt">Table of n, a(n) for n = 0..10000</a>
%H A231503 Jean Coquet, <a href="https://doi.org/10.1016/0022-314X(86)90067-3">Power sums of digital sums</a>, J. Number Theory, Vol. 22, No. 2 (1986), pp. 161-176.
%H A231503 P. J. Grabner, P. Kirschenhofer, H. Prodinger and R. F. Tichy, <a href="http://math.sun.ac.za/~hproding/abstract/abs_80.htm">On the moments of the sum-of-digits function</a>, <a href="http://math.sun.ac.za/~hproding/pdffiles/st_andrews.pdf">PDF</a>, Applications of Fibonacci numbers, Vol. 5 (St. Andrews, 1992), Kluwer Acad. Publ., Dordrecht, 1993, pp. 263-271.
%H A231503 J.-L. Mauclaire and Leo Murata, <a href="https://dx.doi.org/10.3792/pjaa.59.274">On q-additive functions. I</a>, Proc. Japan Acad. Ser. A Math. Sci., Vol. 59, No. 6 (1983), pp. 274-276.
%H A231503 J.-L. Mauclaire and Leo Murata, <a href="https://dx.doi.org/10.3792/pjaa.59.441">On q-additive functions. II</a>, Proc. Japan Acad. Ser. A Math. Sci., Vol. 59, No. 9 (1983), pp. 441-444.
%H A231503 J. R. Trollope, <a href="http://www.jstor.org/stable/2687954">An explicit expression for binary digital sums</a>, Math. Mag., Vol. 41, No. 1 (1968), pp. 21-25.
%t A231503 Accumulate @ (Table[Plus @@ IntegerDigits[n, 3], {n, 0, 75}]^2) (* _Amiram Eldar_, Jan 20 2022 *)
%o A231503 (PARI) a(n) = sum(i=0, n, sumdigits(i, 3)^2); \\ _Michel Marcus_, Sep 20 2017
%Y A231503 Cf. A053735, A094345, A231504, A231505.
%K A231503 nonn,base
%O A231503 0,3
%A A231503 _N. J. A. Sloane_, Nov 13 2013