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 A107129 #36 Oct 26 2015 13:12:56 %S A107129 1,3,5,10,21,36,60,80,120,180,252,300,720,1080,1440,1680,2160,2520, %T A107129 3600,5040,7560,9240,10080,12600,15120,18480,25200,27720,36960,41580, %U A107129 45360,50400,55440,83160,110880,131040,166320,221760,277200,332640,360360 %N A107129 Numbers n which are palindromic in more bases b, 1<b<n, than any previous number. %C A107129 Records by number in A037183, by indices in A065531. %C A107129 Except for 3, 5 and 21 they are all even and except for the first seven, they are all multiples of twelve. %D A107129 Michael Trott, The Mathematica GuideBook for Programming, Springer, 2004, page 218. %H A107129 Robert G. Wilson v, <a href="/A107129/b107129.txt">Table of n, a(n) for n = 0..91</a> %e A107129 1 has no palindromic representation in bases 2 to n. %e A107129 3 = 11_2. %e A107129 5 = 101_2, 11_4. %e A107129 10 = 101_3, 22_4, 11_9. %e A107129 21 = 10101_2, 111_4, 33_6, 11_20. %e A107129 36960 = 5775_19, 3(90)3_97, (176)(176)_209, (168)(168)_219, %e A107129 (165)(165)_223, (160)(160)_230, (154)(154)_239, (140)(140)_263, (132)(132)_279, %e A107129 (120)(120)_307, (112)(112)_329, (110)(110)_335, (105)(105)_351, (96)(96)_384, %e A107129 (88)(88)_419, (84)(84)_439, (80)(80)_461, (77)(77)_479, (70)(70)_527, %e A107129 (66)(66)_559, (60)(60)_615, (56)(56)_659, (55)(55)_671, (48)(48)_769, %e A107129 (44)(44)_839, (42)(42)_879, (40)(40)_923, (35)(35)_1055, (33)(33)_1119, %e A107129 (32)(32)_1154, (30)(30)_1231, (28)(28)_1319, (24)(24)_1539, (22)(22)_1679, %e A107129 (21)(21)_1759, (20)(20)_1847, (16)(16)_2309, (15)(15)_2463, (14)(14)_2639, %e A107129 (12)(12)_3079, (11)(11)_3359, (10)(10)_3695, 88_4619, 77_5279, 66_6159, 55_7391, %e A107129 44_9239, 33_12319, 22_18479, 11_36959. %t A107129 f[n_] := Block[{s = Floor@ Sqrt[n + 1] - 1, b = 2, c = If[IntegerQ@ Sqrt[n + 1], -2, -1]}, While[b < s + 2, idn = IntegerDigits[n, b]; If[ idn == Reverse@ idn, c++]; b++]; c + Count[ Mod[n, Range@ s], 0]]; f[n_] := 0 /; n < 3; %t A107129 k = 0; mx = -1; lst = {}; While[ k < 360000001, c = f@ k; If[ c > mx, AppendTo[lst, k]; mx = c]; k++]; lst %Y A107129 Cf. A037183, A065531, A106801, A135549. %K A107129 nonn,base %O A107129 0,2 %A A107129 Michael Trott (mtrott(AT)wolfram.com) and _Robert G. Wilson v_, May 12 2005