A097262 Numbers whose set of base 16 digits is {0,F}, where F base 16 = 15 base 10.

0, 15, 240, 255, 3840, 3855, 4080, 4095, 61440, 61455, 61680, 61695, 65280, 65295, 65520, 65535, 983040, 983055, 983280, 983295, 986880, 986895, 987120, 987135, 1044480, 1044495, 1044720, 1044735, 1048320, 1048335, 1048560, 1048575

Offset

0,2

Comments

n such that there exists a permutation p_1, ..., p_n of 1, ..., n such that i + p_i is a power of 16 for every i.

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Formula

a(n) = 15*A033052(n).

a(2n) = 16*a(n), a(2n+1) = a(2n)+15.

Mathematica

f[n_] := FromDigits[ IntegerDigits[n, 2] /. {1 -> 15}, 16]; Array[f, 32, 0] (* or *)
FromDigits[#, 16] & /@ Tuples[{0, 15}, 6] (* Harvey P. Dale, Sep 22 2011 *) (* or much slower *)
fQ[n_] := Union@ Join[{0, 15}, IntegerDigits[n, 16]] == {0, 15}; Select[ Range[0, 11000000 ], fQ] (* Robert G. Wilson v, May 12 2012 *)

Prog

(Magma) [n: n in [0..1110000] | Set(IntegerToSequence(n, 16)) subset {0, 15}]; // Vincenzo Librandi, Jun 05 2012

Crossrefs

Cf. A001196, A005823, A097251-A097261.

Sequence in context: A071811 A157456 A343527 * A158557 A220821 A090411

Adjacent sequences: A097259 A097260 A097261 * A097263 A097264 A097265

Keyword

nonn,base

Author

Ray Chandler, Aug 03 2004

Status

approved