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.

Showing 1-2 of 2 results.

A199238 n mod (number of ones in binary representation of n).

Original entry on oeis.org

0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 2, 0, 1, 2, 3, 0, 1, 0, 1, 0, 0, 1, 3, 0, 1, 2, 3, 1, 1, 2, 1, 0, 1, 0, 2, 0, 1, 2, 3, 0, 2, 0, 3, 2, 1, 2, 2, 0, 1, 2, 3, 1, 1, 2, 0, 2, 1, 2, 4, 0, 1, 2, 3, 0, 1, 0, 1, 0, 0, 1, 3, 0, 1, 2, 3, 1, 1, 2, 4, 0, 0, 1, 3, 0, 1, 2
Offset: 1

Views

Author

Reinhard Zumkeller, Nov 04 2011

Keywords

Comments

a(A049445(n)) = 0;
a(n) = n - A161764(n);
a(A199262(n)) = n and a(m) <> n for m < A199262(n).

Crossrefs

Programs

  • Haskell
    a199238 n = a199238_list !! (n-1)
    a199238_list = zipWith mod [1..] $ tail a000120_list
    
  • Mathematica
    Mod[#,DigitCount[#,2,1]]&/@Range[90] (* Harvey P. Dale, Nov 08 2011 *)
  • PARI
    A199238(n)=n%norml2(binary(n))  \\ M. F. Hasler, Oct 09 2012

A138791 Least number k such that A070635(k) = n.

Original entry on oeis.org

1, 11, 16, 15, 14, 38, 34, 29, 28, 19, 49, 76, 68, 98, 269, 79, 458, 397, 379, 299, 779, 769, 689, 898, 799, 3889, 4898, 5599, 6698, 7996, 8798, 9599, 19888, 16999, 18899, 67979, 58898, 39899, 59998, 49999, 89789, 189989, 89998, 98999, 489898, 298999
Offset: 0

Views

Author

Robert G. Wilson v, Mar 29 2008

Keywords

Comments

A070635(a(n)) = n and A070635(m) <> n for m < a(n).
Least k such that k mod A007953(k) = n. - Robert Israel, Dec 29 2015

Examples

			a(2) = 16: 1+6 = 7 and 16 mod 7 = 2. - _Robert Israel_, Dec 30 2015
		

Crossrefs

Programs

  • Haskell
    a199263 n = (fromJust $ elemIndex n a070635_list) + 1
    -- Reinhard Zumkeller, Nov 07 2011
  • Maple
    extend:= proc(d, x, sx)
    global A, nmin;
    local y, n, tmax;
    if d = 0 then
        n:= x mod sx;
        if not assigned(A[n]) then
           A[n]:= x;
           if n = nmin then
             for nmin from n while assigned(A[nmin]) do od:
           fi;
        fi
    else
      tmax:= 9*d + sx;
      if nmin >= tmax then return fi;
      for y from max(0, nmin + 10 - tmax) to 9 do
        procname(d-1,10*x+y,sx+y)
      od:
    fi
    end proc:
    A[0]:= 1:
    nmin:= 1:
    for d from 2 while nmin < 101 do
       extend(d,0,0)
    od:
    seq(A[i],i=0..nmin-1); # Robert Israel, Dec 29 2015
  • Mathematica
    t = Table[0, {100}]; Do[ a = Mod[n, Plus @@ IntegerDigits@n]; If[a < 100 && t[[a + 1]] == 0, t[[a + 1]] = n; Print[{a, n}]], {n, 2^31}]
    lnk[n_]:=Module[{k=1},While[Mod[k,Total[IntegerDigits[k]]]!=n,k++];k]; Array[lnk, 50, 0] (* Harvey P. Dale, Oct 11 2014 *)

Extensions

Definition corrected by Robert Israel, Dec 29 2015
Showing 1-2 of 2 results.