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A161601 Positive integers n that are each less than the value of the reversal of n's representation in binary. 2
11, 19, 23, 35, 37, 39, 43, 47, 55, 67, 69, 71, 75, 77, 79, 83, 87, 91, 95, 103, 111, 131, 133, 135, 137, 139, 141, 143, 147, 149, 151, 155, 157, 159, 163, 167, 171, 173, 175, 179, 183, 187, 191, 199, 203, 207, 215, 223, 239, 259, 261, 263, 265, 267, 269, 271 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

By "reversal" of n's representation in binary, it is meant: write n in binary (without its leading 0's) from most significant digits on the right and least significant digits on the left, instead of writing n from left to right as is usual. Then interpret the new integer by reading it from left to right.

This sequence contains only odd integers.

EXAMPLE

37 in binary is 100101. Its digital reversal is 101001, which is 41 in decimal. Since 41 > 37, then 37 is in this sequence.

MAPLE

a := proc (n) local n2, sz, rv: n2 := convert(n, base, 2): sz := nops(n2): rv := add(n2[j]*2^(sz-j), j = 1 .. sz): if n < rv then n else end if end proc; seq(a(n), n = 1 .. 280); [From Emeric Deutsch (deutsch(AT)duke.poly.edu), Jun 28 2009]

CROSSREFS

A030101, A006995, A161602, A161603

Sequence in context: A161504 A165947 A129517 * A031406 A105908 A084654

Adjacent sequences:  A161598 A161599 A161600 * A161602 A161603 A161604

KEYWORD

base,nonn

AUTHOR

Leroy Quet, Jun 14 2009

EXTENSIONS

Extended by Emeric Deutsch (deutsch(AT)duke.poly.edu), Jun 28 2009

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Last modified February 15 21:56 EST 2012. Contains 205860 sequences.