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 1-9 of 9 results.

A107778 a(1)=7, a(n) = smallest integer not previously used which contains a digit from a(n-1).

Original entry on oeis.org

7, 17, 1, 10, 0, 20, 2, 12, 11, 13, 3, 23, 21, 14, 4, 24, 22, 25, 5, 15, 16, 6, 26, 27, 28, 8, 18, 19, 9, 29, 32, 30, 31, 33, 34, 35, 36, 37, 38, 39, 43, 40, 41, 42, 44, 45, 46, 47, 48, 49, 54, 50, 51, 52, 53, 55, 56, 57, 58, 59, 65, 60, 61, 62, 63, 64, 66, 67, 68, 69, 76, 70
Offset: 1

Views

Author

Eric Angelini & Zak Seidov, May 24 2005

Keywords

Comments

Cf. A107353 a(1)=0, A107772 a(1)=1, A107773 a(1)=2, A107774 a(1)=3, A107775 a(1)=4, A107776 a(1)=5, A107777 a(1)=6, A107779 a(1)=8, A107780 a(1)=9, A107781 a(1)=10

Links

Crossrefs

Cf. A107353, A107772, A107773, A107774, A107775, A107776, A107777, A107779, A107780, A107781.

Programs

  • Maple
    Agenda:= [$0..6,$8..100]: A[1]:= 7: S:= {7}:
for i from 2 do
  found:= false;
  for j from 1 to nops(Agenda) do
    r:= Agenda[j];
    Sr:= convert(convert(r,base,10),set);
    if Sr intersect S <> {} then
        A[i]:= r;
        Agenda:= subsop(j=NULL,Agenda);
        S:= Sr;
        found:= true;
        break
     fi
   od;
   if not found then break fi;
od:
seq(A[n],n=1..i-1); # Robert Israel, Jul 08 2019
  • Mathematica
    f[l_] := Block[{c = 0}, While[ MemberQ[l, c] || Intersection @@ IntegerDigits /@{Last[l], c}=={}, c++ ];Return[Append[l, c]]];Nest[f, {7}, 70] (* Ray Chandler, Jul 19 2005 *)

Formula

From Robert Israel, Jul 09 2019: (Start)
For n >= 29, it appears that a(n) = n-1 except:
a(i*10^k+j) = i*10^k+j-2 if i=1 and 2<=j<=10, or 2<=i<=8 and 2<=j<=i.
a(i*10^k+1) = i*10^k+i-1 for 2<=i<=8 or i=10.
(End)

A107780 a(1)=9, a(n) = smallest integer not previously used which contains a digit from a(n-1).

Original entry on oeis.org

9, 19, 1, 10, 0, 20, 2, 12, 11, 13, 3, 23, 21, 14, 4, 24, 22, 25, 5, 15, 16, 6, 26, 27, 7, 17, 18, 8, 28, 29, 32, 30, 31, 33, 34, 35, 36, 37, 38, 39, 43, 40, 41, 42, 44, 45, 46, 47, 48, 49, 54, 50, 51, 52, 53, 55, 56, 57, 58, 59, 65, 60, 61, 62, 63, 64, 66, 67, 68, 69, 76, 70
Offset: 1

Views

Author

Eric Angelini & Zak Seidov, May 24 2005

Keywords

Links

Crossrefs

Cf. A107353 a(1)=0, A107772 a(1)=1, A107773 a(1)=2, A107774 a(1)=3, A107775 a(1)=4, A107776 a(1)=5, A107777 a(1)=6, A107778 a(1)=7, A107779 a(1)=8, A107781 a(1)=10.

Programs

  • Maple
    S:= [$0..100]:
Res:= 9: S:= subs(9=NULL,S):
digs:= {9}:
while S <> [] do
  found:= false;
  for i from 1 to nops(S) while not found do
    ndigs:= convert(convert(S[i],base,10),set);
    if ndigs intersect digs <> {} then
      found:= true;
      Res:=Res, S[i];
      S:= subsop(i=NULL, S);
      digs:= ndigs;
    fi
  od;
  if not found then break fi;
od:
Res; # Robert Israel, Jan 22 2020
  • Mathematica
    f[l_] := Block[{c = 0}, While[ MemberQ[l, c] || Intersection @@ IntegerDigits /@{Last[l], c}=={}, c++ ];Return[Append[l, c]]];Nest[f, {9}, 70] (* Ray Chandler, Jul 19 2005 *)

A107772 a(1)=1, a(n) = smallest integer not previously used which contains a digit from a(n-1).

Original entry on oeis.org

1, 10, 0, 20, 2, 12, 11, 13, 3, 23, 21, 14, 4, 24, 22, 25, 5, 15, 16, 6, 26, 27, 7, 17, 18, 8, 28, 29, 9, 19, 31, 30, 32, 33, 34, 35, 36, 37, 38, 39, 43, 40, 41, 42, 44, 45, 46, 47, 48, 49, 54, 50, 51, 52, 53, 55, 56, 57, 58, 59, 65, 60, 61, 62, 63, 64, 66, 67, 68, 69, 76, 70
Offset: 1

Views

Author

Eric Angelini & Zak Seidov, May 24 2005

Keywords

Comments

Cf. A107353 a(1)=0, A107773 a(1)=2, A107774 a(1)=3, A107775 a(1)=4, A107776 a(1)=5, A107777 a(1)=6, A107778 a(1)=7, A107779 a(1)=8, A107780 a(1)=9, A107781 a(1)=10

Crossrefs

Cf. A107353, A107773, A107774, A107775, A107776, A107777, A107778, A107779, A107780, A107781.

Programs

  • Mathematica
    f[l_] := Block[{c = 0}, While[ MemberQ[l, c] || Intersection @@ IntegerDigits /@{Last[l], c}=={}, c++ ];Return[Append[l, c]]];Nest[f, {1}, 70] (* Ray Chandler, Jul 19 2005 *)

A107773 a(1)=2, a(n) = smallest integer not previously used which contains a digit from a(n-1).

Original entry on oeis.org

2, 12, 1, 10, 0, 20, 21, 11, 13, 3, 23, 22, 24, 4, 14, 15, 5, 25, 26, 6, 16, 17, 7, 27, 28, 8, 18, 19, 9, 29, 32, 30, 31, 33, 34, 35, 36, 37, 38, 39, 43, 40, 41, 42, 44, 45, 46, 47, 48, 49, 54, 50, 51, 52, 53, 55, 56, 57, 58, 59, 65, 60, 61, 62, 63, 64, 66, 67, 68, 69, 76, 70
Offset: 1

Views

Author

Eric Angelini & Zak Seidov, May 24 2005

Keywords

Comments

Cf. A107353 a(1)=0, A107772 a(1)=1, A107774 a(1)=3, A107775 a(1)=4, A107776 a(1)=5, A107777 a(1)=6, A107778 a(1)=7, A107779 a(1)=8, A107780 a(1)=9, A107781 a(1)=10

Crossrefs

Cf. A107353, A107772, A107774, A107775, A107776, A107777, A107778, A107779, A107780, A107781.

Programs

  • Mathematica
    f[l_] := Block[{c = 0}, While[ MemberQ[l, c] || Intersection @@ IntegerDigits /@{Last[l], c}=={}, c++ ];Return[Append[l, c]]];Nest[f, {2}, 70] (* Ray Chandler, Jul 19 2005 *)

A107774 a(1)=3, a(n) = smallest integer not previously used which contains a digit from a(n-1).

Original entry on oeis.org

3, 13, 1, 10, 0, 20, 2, 12, 11, 14, 4, 24, 21, 15, 5, 25, 22, 23, 26, 6, 16, 17, 7, 27, 28, 8, 18, 19, 9, 29, 32, 30, 31, 33, 34, 35, 36, 37, 38, 39, 43, 40, 41, 42, 44, 45, 46, 47, 48, 49, 54, 50, 51, 52, 53, 55, 56, 57, 58, 59, 65, 60, 61, 62, 63, 64, 66, 67, 68, 69, 76, 70
Offset: 1

Views

Author

Eric Angelini & Zak Seidov, May 24 2005

Keywords

Comments

Cf. A107353 a(1)=0, A107772 a(1)=1, A107773 a(1)=2, A107775 a(1)=4, A107776 a(1)=5, A107777 a(1)=6, A107778 a(1)=7, A107779 a(1)=8, A107780 a(1)=9, A107781 a(1)=10

Crossrefs

Cf. A107353, A107772, A107773, A107775, A107776, A107777, A107778, A107779, A107780, A107781.

Programs

  • Mathematica
    f[l_] := Block[{c = 0}, While[ MemberQ[l, c] || Intersection @@ IntegerDigits /@{Last[l], c}=={}, c++ ];Return[Append[l, c]]];Nest[f, {3}, 70] (* Ray Chandler, Jul 19 2005 *)

A107776 a(1)=5, a(n) = smallest integer not previously used which contains a digit from a(n-1).

Original entry on oeis.org

5, 15, 1, 10, 0, 20, 2, 12, 11, 13, 3, 23, 21, 14, 4, 24, 22, 25, 26, 6, 16, 17, 7, 27, 28, 8, 18, 19, 9, 29, 32, 30, 31, 33, 34, 35, 36, 37, 38, 39, 43, 40, 41, 42, 44, 45, 46, 47, 48, 49, 54, 50, 51, 52, 53, 55, 56, 57, 58, 59, 65, 60, 61, 62, 63, 64, 66, 67, 68, 69, 76, 70
Offset: 1

Views

Author

Eric Angelini & Zak Seidov, May 24 2005

Keywords

Comments

Cf. A107353 a(1)=0, A107772 a(1)=1, A107773 a(1)=2, A107774 a(1)=3, A107775 a(1)=4, A107777 a(1)=6, A107778 a(1)=7, A107779 a(1)=8, A107780 a(1)=9, A107781 a(1)=10

Crossrefs

Cf. A107353, A107772, A107773, A107774, A107775, A107777, A107778, A107779, A107780, A107781.

Programs

  • Mathematica
    f[l_] := Block[{c = 0}, While[ MemberQ[l, c] || Intersection @@ IntegerDigits /@{Last[l], c}=={}, c++ ];Return[Append[l, c]]];Nest[f, {5}, 70] (* Ray Chandler, Jul 19 2005 *)

A107777 a(1)=6, a(n) = smallest integer not previously used which contains a digit from a(n-1).

Original entry on oeis.org

6, 16, 1, 10, 0, 20, 2, 12, 11, 13, 3, 23, 21, 14, 4, 24, 22, 25, 5, 15, 17, 7, 27, 26, 28, 8, 18, 19, 9, 29, 32, 30, 31, 33, 34, 35, 36, 37, 38, 39, 43, 40, 41, 42, 44, 45, 46, 47, 48, 49, 54, 50, 51, 52, 53, 55, 56, 57, 58, 59, 65, 60, 61, 62, 63, 64, 66, 67, 68, 69, 76, 70
Offset: 1

Views

Author

Eric Angelini & Zak Seidov, May 24 2005

Keywords

Comments

Cf. A107353 a(1)=0, A107772 a(1)=1, A107773 a(1)=2, A107774 a(1)=3, A107775 a(1)=4, A107776 a(1)=5, A107778 a(1)=7, A107779 a(1)=8, A107780 a(1)=9, A107781 a(1)=10

Crossrefs

Cf. A107353, A107772, A107773, A107774, A107775, A107776, A107778, A107779, A107780, A107781.

Programs

  • Mathematica
    f[l_] := Block[{c = 0}, While[ MemberQ[l, c] || Intersection @@ IntegerDigits /@{Last[l], c}=={}, c++ ];Return[Append[l, c]]];Nest[f, {6}, 70] (* Ray Chandler, Jul 19 2005 *)

A107779 a(1)=8, a(n) = smallest integer not previously used which contains a digit from a(n-1).

Original entry on oeis.org

8, 18, 1, 10, 0, 20, 2, 12, 11, 13, 3, 23, 21, 14, 4, 24, 22, 25, 5, 15, 16, 6, 26, 27, 7, 17, 19, 9, 29, 28, 32, 30, 31, 33, 34, 35, 36, 37, 38, 39, 43, 40, 41, 42, 44, 45, 46, 47, 48, 49, 54, 50, 51, 52, 53, 55, 56, 57, 58, 59, 65, 60, 61, 62, 63, 64, 66, 67, 68, 69, 76, 70
Offset: 1

Views

Author

Eric Angelini & Zak Seidov, May 24 2005

Keywords

Comments

Cf. A107353 a(1)=0, A107772 a(1)=1, A107773 a(1)=2, A107774 a(1)=3, A107775 a(1)=4, A107776 a(1)=5, A107777 a(1)=6, A107778 a(1)=7, A107780 a(1)=9, A107781 a(1)=10

Crossrefs

Cf. A107353, A107772, A107773, A107774, A107775, A107776, A107777, A107778, A107780, A107781.

Programs

  • Mathematica
    f[l_] := Block[{c = 0}, While[ MemberQ[l, c] || Intersection @@ IntegerDigits /@{Last[l], c}=={}, c++ ];Return[Append[l, c]]];Nest[f, {8}, 70] (* Ray Chandler, Jul 19 2005 *)

A107781 a(1)=10, a(n) = smallest integer not previously used which contains a digit from a(n-1).

Original entry on oeis.org

10, 0, 20, 2, 12, 1, 11, 13, 3, 23, 21, 14, 4, 24, 22, 25, 5, 15, 16, 6, 26, 27, 7, 17, 18, 8, 28, 29, 9, 19, 31, 30, 32, 33, 34, 35, 36, 37, 38, 39, 43, 40, 41, 42, 44, 45, 46, 47, 48, 49, 54, 50, 51, 52, 53, 55, 56, 57, 58, 59, 65, 60, 61, 62, 63, 64, 66, 67, 68, 69, 76, 70
Offset: 1

Views

Author

Eric Angelini & Zak Seidov, May 24 2005

Keywords

Comments

Cf. A107353 a(1)=0, A107772 a(1)=1, A107773 a(1)=2, A107774 a(1)=3, A107775 a(1)=4, A107776 a(1)=5, A107777 a(1)=6, A107778 a(1)=7, A107779 a(1)=8, A107780 a(1)=9

Crossrefs

Cf. A107353, A107772, A107773, A107774, A107775, A107776, A107777, A107778, A107779, A107780.

Programs

  • Mathematica
    f[l_] := Block[{c = 0}, While[ MemberQ[l, c] || Intersection @@ IntegerDigits /@{Last[l], c}=={}, c++ ];Return[Append[l, c]]];Nest[f, {10}, 70] (* Ray Chandler, Jul 19 2005 *)
Showing 1-9 of 9 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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