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A091017 Nonpalindromic integers which have an even number of ones in binary and whose reverse does as well. 1
15, 17, 27, 29, 30, 34, 36, 43, 45, 51, 54, 57, 58, 60, 63, 68, 71, 72, 75, 85, 86, 90, 92, 102, 108, 113, 114, 126, 129, 132, 135, 139, 144, 147, 150, 159, 165, 170, 175, 177, 192, 195, 197, 198, 201, 204, 210, 216, 219, 226, 228, 231, 237, 264, 270, 288, 291 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

15 is a term because 15_10 = 1111_2 has 4 1's and 51_10 = 110011_2 also has 4 1's.

MAPLE

filter:= proc(n) local L, r, j;

  L:= convert(n, base, 10);

  r:= add(L[-j]*10^(j-1), j=1..nops(L));

  r <> n and convert(convert(n, base, 2), `+`)::even  and convert(convert(r, base, 2), `+`)::even

end proc:

select(filter, [$1..1000]); # Robert Israel, May 11 2021

MATHEMATICA

Reveral[n_] := FromDigits[ Reverse[ IntegerDigits[ n]]]; Select[ Range[ 296], Reveral[ # ] != # && EvenQ[ Count[ IntegerDigits[ #, 2], 1]] && EvenQ[ Count[ IntegerDigits[ Reveral[ # ], 2], 1]] &] (* Robert G. Wilson v, Feb 26 2004 *)

CROSSREFS

Cf. A006567, A001969, A000040.

Sequence in context: A124334 A002155 A290749 * A157716 A113968 A093812

Adjacent sequences:  A091014 A091015 A091016 * A091018 A091019 A091020

KEYWORD

easy,nonn,base

AUTHOR

Michael Joseph Halm, Feb 25 2004

EXTENSIONS

Edited, corrected and extended by Robert G. Wilson v, Feb 26 2004

STATUS

approved

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Last modified June 15 13:25 EDT 2021. Contains 345048 sequences. (Running on oeis4.)