A329419 - OEIS

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A329419

Numbers all of whose divisors are binary palindromes.

1, 3, 5, 7, 9, 15, 17, 21, 27, 31, 45, 51, 63, 73, 85, 93, 107, 119, 127, 153, 189, 219, 255, 257, 313, 365, 381, 443, 511, 765, 771, 1193, 1241, 1285, 1453, 1533, 1571, 1619, 1787, 1799, 1831, 1879, 2313, 3579, 3855, 4369, 4889, 5113, 5189, 5397, 5557, 5869

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OFFSET

1,2

COMMENTS

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

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

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.

MATHEMATICA

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

CROSSREFS