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A163170 Odd composite integers that are palindromes when written in binary. 0
9, 15, 21, 27, 33, 45, 51, 63, 65, 85, 93, 99, 119, 129, 153, 165, 189, 195, 219, 231, 255, 273, 297, 325, 341, 365, 381, 387, 403, 427, 455, 471, 495, 511, 513, 561, 585, 633, 645, 693, 717, 765, 771, 819, 843, 891, 903, 951, 975, 1023, 1025, 1057, 1105, 1137 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..54.

MAPLE

rev := proc (n) local nn: nn := convert(n, base, 10): add(nn[j]*10^(nops(nn)-j), j = 1 .. nops(nn)) end proc: a := proc (n) local n2: n2 := convert(n, binary): if 1 < n and `mod`(n, 2) = 1 and isprime(n) = false and rev(n2) = n2 then n else end if end proc: seq(a(n), n = 1 .. 1500); # Emeric Deutsch, Jul 24 2009

CROSSREFS

Cf. A016041.

Sequence in context: A225461 A172181 A063139 * A097636 A179384 A225513

Adjacent sequences:  A163167 A163168 A163169 * A163171 A163172 A163173

KEYWORD

base,nonn

AUTHOR

Leroy Quet, Jul 22 2009

EXTENSIONS

Extended by Emeric Deutsch, Jul 24 2009

STATUS

approved

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Last modified September 16 11:30 EDT 2021. Contains 347472 sequences. (Running on oeis4.)