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A356396 Nonnegative numbers k such that the negaFibonacci representation of -k (A215023(k)) is palindromic.

%I A356396 #5 Aug 07 2022 07:52:37
%S A356396 0,2,7,20,26,44,54,73,112,143,159,196,212,264,290,350,376,426,492,518,
%T A356396 568,675,756,798,905,986,1028,1125,1167,1280,1361,1403,1500,1542,1683,
%U A356396 1751,1908,1976,2107,2290,2358,2515,2583,2714,2887,2955,3086,3275,3343
%N A356396 Nonnegative numbers k such that the negaFibonacci representation of -k (A215023(k)) is palindromic.
%C A356396 See A094202 and A356395 for similar sequences.
%H A356396 Wikipedia, <a href="https://en.wikipedia.org/wiki/NegaFibonacci_coding">NegaFibonacci coding</a>
%H A356396 <a href="/index/Z#Zeckendorf">Index entries for sequences related to Zeckendorf expansion of n</a>
%e A356396 The first terms are:
%e A356396   n   a(n)  A215023(a(n))
%e A356396   --  ----  -------------
%e A356396    1     0              0
%e A356396    2     2           1001
%e A356396    3     7         100001
%e A356396    4    20       10000001
%e A356396    5    26       10100101
%e A356396    6    44     1001001001
%e A356396    7    54     1000000001
%e A356396    8    73     1010000101
%e A356396    9   112   100100001001
%e A356396   10   143   100000000001
%o A356396 (PARI) is(n) = { my (v=0, neg=0, pos=0, f); n=-n; for (e=0, oo, f=fibonacci(-1-e); if (f<0, neg+=f, pos+=f); if (neg <=n && n <= pos, while (n, if (f<0, neg-=f, pos-=f); if (neg > n || n > pos, v+=2^e; n-=f); f=fibonacci(-1-e--)); my (b=binary(v)); return (b==Vecrev(b)))) }
%Y A356396 Cf. A094202, A215023, A356395.
%K A356396 nonn,base
%O A356396 1,2
%A A356396 _Rémy Sigrist_, Aug 05 2022