cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A169810 a(n) = n XOR n^2.

Original entry on oeis.org

0, 0, 6, 10, 20, 28, 34, 54, 72, 88, 110, 114, 156, 164, 202, 238, 272, 304, 342, 378, 388, 428, 498, 518, 600, 616, 702, 706, 780, 852, 922, 990, 1056, 1120, 1190, 1258, 1332, 1404, 1410, 1494, 1640, 1720, 1742, 1810, 1980, 1988, 2154, 2190, 2352, 2384, 2550, 2586
Offset: 0

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Author

N. J. A. Sloane, May 28 2010

Keywords

Comments

XOR the binary representations of n and n^2.

Examples

			a(5) = 28:
..101 <- 5
11001 <- 25
----- <- XOR
11100 -> 28
		

Crossrefs

Suggested by A174375. Cf. A070883, A169811-A169814.
Cf. A007745 (OR), A213541 (AND), A002378.

Programs

  • Haskell
    import Data.Bits (xor)
    a169810 n = n ^ 2 `xor` n :: Integer
    -- Reinhard Zumkeller, Dec 27 2012
    
  • Maple
    f:=proc(n) local i,t0,t1,t2,ts,tl,n1,n2;
    t1:=convert(n,base,2); t2:=convert(n^2,base,2); n1:=nops(t1); n2:=nops(t2);
    if n1 < n2 then ts:= t1; tl:=t2; else ts:=t2; tl:=t1; fi;
    t0:=[]; for i from 1 to nops(ts) do t0:=[op(t0), (ts[i] + tl[i]) mod 2 ]; od:
    for i from nops(ts)+1 to nops(tl) do t0:=[op(t0), tl[i]]; od:
    add(2^(i-1)*t0[i], i=1..nops(t0)); end;
    # second Maple program:
    a:= n-> Bits[Xor](n, n^2):
    seq(a(n), n=0..100);  # Alois P. Heinz, Mar 29 2018
  • Mathematica
    a[n_]:=BitXor[n, n^2]; Array[a, 60, 0] (* Robert G. Wilson v, Jun 09 2010 *)
  • PARI
    A169810(n)=bitxor(n^2,n) \\ M. F. Hasler, May 07 2023
    
  • Python
    A169810=lambda n:n**2^n # M. F. Hasler, May 07 2023