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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.

A352087 Numbers whose minimal (or greedy) tribonacci representation (A278038) is palindromic.

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%I A352087 #9 Mar 05 2022 04:02:20
%S A352087 0,1,3,5,8,14,18,23,25,36,40,45,52,62,71,78,82,102,110,128,148,150,
%T A352087 163,181,198,211,229,233,246,264,275,312,326,360,397,411,426,463,477,
%U A352087 505,529,562,593,617,650,658,682,715,746,770,781,805,838,869,893,926,928
%N A352087 Numbers whose minimal (or greedy) tribonacci representation (A278038) is palindromic.
%C A352087 A000073(n) + 1 is a term for n>=4, since its minimal tribonacci representation is 10...01 with n-4 0's between the two 1's.
%H A352087 Amiram Eldar, <a href="/A352087/b352087.txt">Table of n, a(n) for n = 1..10000</a>
%e A352087 The first 10 terms are:
%e A352087    n  a(n)  A278038(a(n))
%e A352087   -----------------------
%e A352087    1   0                0
%e A352087    2   1                1
%e A352087    3   3               11
%e A352087    4   5              101
%e A352087    5   8             1001
%e A352087    6  14            10001
%e A352087    7  18            10101
%e A352087    8  23            11011
%e A352087    9  25           100001
%e A352087   10  36           101101
%t A352087 t[1] = 1; t[2] = 2; t[3] = 4; t[n_] := t[n] = t[n - 1] + t[n - 2] + t[n - 3]; q[n_] := Module[{s = {}, m = n, k}, While[m > 0, k = 1; While[t[k] <= m, k++]; k--; AppendTo[s, k]; m -= t[k]; k = 1]; PalindromeQ[FromDigits @ IntegerDigits[Total[2^(s - 1)], 2]]]; Select[Range[0, 1000], q]
%Y A352087 Cf. A000073, A278038.
%Y A352087 Similar sequences: A002113, A006995, A014190, A094202, A331191, A351712, A351717.
%K A352087 nonn,base
%O A352087 1,3
%A A352087 _Amiram Eldar_, Mar 04 2022