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 A079495 #8 Aug 18 2025 00:09:11
%S A079495 0,13,14,16,17,22,23,25,26,31,32,34,35,37,38,39,42,46,47,48,51,58,59,
%T A079495 61,62,64,65,66,69,73,74,75,78,85,86,88,89,91,92,93,96,100,101,102,
%U A079495 105,109,110,111,114,117,126,136,137,138,141,144,153,166,167,169,170,172,173
%N A079495 Numbers k such that the sum of the squares of the digits of k in base 3 is 0 (mod 3).
%C A079495 In base 2 this gives the "Evil Numbers" (cf. A001969) and slope 2. One may conjecture that in base b the asymptotic slope will be b and might suspect asymptotic density 1/b for each result (mod b). For nonprime b larger variations occur and "very big" numbers must be considered to believe in the conjecture (1 million or more...). (Related to A006287, here mod b is considered)
%e A079495 59 is a member because 59 = 2013_3 and 2^2+0^2+1^2+1^2 = 6 = 0 (mod 3).
%t A079495 Ev = Function[{b, x}, vx = IntegerDigits[x, b]; Mod[vx.vx, b]]; Seq = Function[{b, n}, Flatten[Position[Table[Ev[b, k], {k, 1, n}], 0]]]; Seq[3, 1000]
%Y A079495 Cf. A001969, A006287, A075311.
%K A079495 base,easy,nonn
%O A079495 1,2
%A A079495 _Carlos Alves_, Jan 20 2003
%E A079495 Revised by _Sean A. Irvine_, Aug 17 2025