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 A329419 Numbers all of whose divisors are binary palindromes. 10

%I

%S 1,3,5,7,9,15,17,21,27,31,45,51,63,73,85,93,107,119,127,153,189,219,

%T 255,257,313,365,381,443,511,765,771,1193,1241,1285,1453,1533,1571,

%U 1619,1787,1799,1831,1879,2313,3579,3855,4369,4889,5113,5189,5397,5557,5869

%N Numbers all of whose divisors are binary palindromes.

%C Subsequence of A163410, and differs from it from n = 65.

%H Amiram Eldar, <a href="/A329419/b329419.txt">Table of n, a(n) for n = 1..10000</a>

%e 15 is in the sequence since the binary representations of its divisors, 1, 3, 5, and 15, are all palindromes: 1, 11, 101, and 1111.

%t binPalQ[n_] := PalindromeQ @ IntegerDigits[n, 2]; seqQ[n_] := binPalQ[n] && AllTrue[Most @ Divisors[n], binPalQ]; Select[Range[10^4], seqQ]

%Y Cf. A006995, A062687, A163410.

%Y Supersequence of A016041.

%K nonn,base

%O 1,2

%A _Amiram Eldar_, Nov 29 2019

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Last modified November 30 12:28 EST 2021. Contains 349419 sequences. (Running on oeis4.)