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.

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A190809 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x and 3x+2 are in a.

Original entry on oeis.org

1, 2, 4, 5, 8, 10, 14, 16, 17, 20, 26, 28, 32, 34, 40, 44, 50, 52, 53, 56, 62, 64, 68, 80, 86, 88, 98, 100, 104, 106, 112, 122, 124, 128, 134, 136, 152, 158, 160, 161, 170, 172, 176, 188, 194, 196, 200, 206, 208, 212, 224, 242, 244, 248, 256, 260, 266, 268, 272, 296
Offset: 1

Views

Author

Clark Kimberling, May 20 2011

Keywords

Comments

See A190803.

Links

Crossrefs

Cf. A190803, A190853, A190854.

Programs

  • Haskell
    import Data.Set (singleton, deleteFindMin, insert)
a190809 n = a190809_list !! (n-1)
a190809_list = f $ singleton 1
   where f s = m : (f $ insert (2*m) $ insert (3*m+2) s')
             where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011
  • Mathematica
    h = 2; i = 0; j = 3; k = 2; f = 1; g = 9 ;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A190809 *)
b = a/2; c = (a - 2)/3; r = Range[1, 900];
d = Intersection[b, r] (* A190853 *)
e = Intersection[c, r] (* A190854 *)

Extensions

a(51)=224 inserted by Reinhard Zumkeller, Jun 01 2011

A190810 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x+1 and 3x-1 are in a.

Original entry on oeis.org

1, 2, 3, 5, 7, 8, 11, 14, 15, 17, 20, 23, 29, 31, 32, 35, 41, 44, 47, 50, 59, 63, 65, 68, 71, 83, 86, 89, 92, 95, 101, 104, 119, 122, 127, 131, 137, 140, 143, 149, 167, 173, 176, 179, 185, 188, 191, 194, 203, 209, 212, 239, 245, 248, 255, 257, 263, 266, 275, 281
Offset: 1

Views

Author

Clark Kimberling, May 20 2011

Keywords

Comments

See A190803.

Links

Crossrefs

Cf. A190803, A190855, A190856.

Programs

  • Haskell
    import Data.Set (singleton, deleteFindMin, insert)
a190810 n = a190810_list !! (n-1)
a190810_list = f $ singleton 1
   where f s = m : (f $ insert (2*m+1) $ insert (3*m-1) s')
             where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011
  • Mathematica
    h = 2; i = 1; j = 3; k = -1; f = 1; g = 9 ;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A190810 *)
b = (a - 1)/2; c = (a + 1)/3; r = Range[1, 900];
d = Intersection[b, r] (* A190855 *)
e = Intersection[c, r] (* A190856 *)
  • PARI
    is(n)=if(n<7, n!=4, (n%3==1 && is(n\3)) || (n%2 && is(n\2))) \\ Charles R Greathouse IV, Jul 14 2016

Extensions

a(55)=255 inserted by Reinhard Zumkeller, Jun 01 2011

A190856 Integers in (1+A190810)/3; contains A190810 as a proper subsequence.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 14, 15, 16, 17, 20, 22, 23, 24, 28, 29, 30, 31, 32, 34, 35, 40, 41, 44, 46, 47, 48, 50, 56, 58, 59, 60, 62, 63, 64, 65, 68, 70, 71, 80, 82, 83, 86, 88, 89, 92, 94, 95, 96, 100, 101, 104, 112, 116, 118, 119, 120, 122, 124, 126, 127, 128, 130, 131, 136, 137, 140, 142, 143, 149, 160, 164, 166, 167, 172, 173
Offset: 1

Views

Author

Clark Kimberling, May 25 2011

Keywords

Comments

See A190803.

Crossrefs

Cf. A190803, A190810, A190856.

Programs

A190805 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x-1 and 3x+1 are in a.

Original entry on oeis.org

1, 4, 7, 13, 22, 25, 40, 43, 49, 67, 76, 79, 85, 97, 121, 130, 133, 148, 151, 157, 169, 193, 202, 229, 238, 241, 256, 259, 265, 292, 295, 301, 313, 337, 364, 385, 391, 400, 403, 445, 454, 457, 472, 475, 481, 508, 511, 517, 529, 580, 583, 589, 601, 607, 625, 673, 688, 715, 724, 727
Offset: 1

Views

Author

Clark Kimberling, May 20 2011

Keywords

Comments

See A190803.

Links

Crossrefs

Cf. A190803, A190845.

Programs

  • Haskell
    import Data.Set (singleton, deleteFindMin, insert)
a190805 n = a190805_list !! (n-1)
a190805_list = 1 : f (singleton 4)
   where f s = m : (f $ insert (2*m-1) $ insert (3*m+1) s')
             where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011
  • Mathematica
    h = 2; i = -1; j = 3; k = 1; f = 1; g = 10 ;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A190805 *)
b = (a + 1)/2; c = (a - 1)/3; r = Range[1, 500];
d = Intersection[b, r] (* A190845 *)
e = Intersection[c, r] (* A190808 conjectured *)

Extensions

a(56)=673 inserted by Reinhard Zumkeller, Jun 01 2011

A190806 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x-1 and 3x+2 are in a.

Original entry on oeis.org

1, 5, 9, 17, 29, 33, 53, 57, 65, 89, 101, 105, 113, 129, 161, 173, 177, 197, 201, 209, 225, 257, 269, 305, 317, 321, 341, 345, 353, 389, 393, 401, 417, 449, 485, 513, 521, 533, 537, 593, 605, 609, 629, 633, 641, 677, 681, 689, 705, 773, 777, 785, 801, 809, 833, 897, 917, 953, 965, 969
Offset: 1

Views

Author

Clark Kimberling, May 20 2011

Keywords

Comments

See A190803.

Links

Crossrefs

Cf. A190803, A190848.

Programs

  • Haskell
    import Data.Set (singleton, deleteFindMin, insert)
a190806 n = a190806_list !! (n-1)
a190806_list = 1 : f (singleton 5)
   where f s = m : (f $ insert (2*m-1) $ insert (3*m+2) s')
             where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011
  • Mathematica
    h = 2; i = -1; j = 3; k = 2; f = 1; g = 12 ;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A190806 *)
b = (a + 1)/2; c = (a - 2)/3; r = Range[1, 1200];
d = Intersection[b, r] (* A190804 conjectured *)
e = Intersection[c, r] (* A190848 *)

Extensions

a(56)=897 inserted by Reinhard Zumkeller, Jun 01 2011

A190811 Increasing sequence generated by these rules: a(1)=1, and if x is in a then 2x+1 and 3x are in a.

Original entry on oeis.org

1, 3, 7, 9, 15, 19, 21, 27, 31, 39, 43, 45, 55, 57, 63, 79, 81, 87, 91, 93, 111, 115, 117, 127, 129, 135, 159, 163, 165, 171, 175, 183, 187, 189, 223, 231, 235, 237, 243, 255, 259, 261, 271, 273, 279, 319, 327, 331, 333, 343, 345, 351, 367, 375, 379, 381, 387, 405, 447, 463, 471, 475, 477, 487, 489, 495, 511, 513, 519, 523, 525, 543
Offset: 1

Views

Author

Clark Kimberling, May 20 2011

Keywords

Comments

See A190803.

Links

Crossrefs

Cf. A190803.

Programs

  • Haskell
    import Data.Set (singleton, deleteFindMin, insert)
a190811 n = a190811_list !! (n-1)
a190811_list = f $ singleton 1
   where f s = m : (f $ insert (2*m+1) $ insert (3*m) s')
             where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Jun 01 2011
  • Mathematica
    h = 2; i = 1; j = 3; k = 0; f = 1; g = 9 ;
a = Union[Flatten[NestList[{h # + i, j # + k} &, f, g]]]  (* A190811 *)
b = (a - 1)/2; c = a/3; r = Range[1, 300];
d = Intersection[b, r] (* A002977 *)
e = Intersection[c, r] (* A190857 *)

A190849 Integers in (A190807)/2; contains A190807 as a proper subsequence.

Original entry on oeis.org

1, 2, 4, 5, 7, 8, 10, 11, 14, 16, 20, 22, 23, 28, 29, 32, 34, 40, 41, 43, 44, 46, 47, 56, 58, 59, 61, 64, 65, 68, 70, 80, 82, 83, 86, 88, 92, 94, 95, 97, 112, 116, 118, 119, 122, 124, 128, 130, 131, 136, 137, 140, 142, 160, 164, 166, 167, 172, 173, 176, 178, 184, 188, 190, 191, 194, 196, 203, 205, 224, 232, 236, 238, 239, 244, 245, 248
Offset: 1

Views

Author

Clark Kimberling, May 25 2011

Keywords

Comments

See A190803.

Crossrefs

Cf. A190803, A190807, A190850.

Programs

  • Mathematica
    Intersection[Union[Flatten[NestList[{2 #, 3 # - 1} &, 1, 9]]]/2, Range[1, 300]]

A190850 Integers in (1+A190807)/3; contains A190807 as a proper subsequence.

Original entry on oeis.org

1, 2, 3, 4, 5, 7, 8, 10, 11, 14, 15, 16, 19, 20, 22, 23, 27, 28, 29, 31, 32, 39, 40, 41, 43, 44, 46, 47, 55, 56, 58, 59, 63, 64, 65, 68, 75, 79, 80, 82, 83, 86, 87, 88, 91, 92, 94, 95, 107, 111, 112, 115, 116, 118, 119, 122, 123, 127, 128, 130, 131, 136, 137, 140, 155, 159, 160, 163, 164, 166, 167, 171, 172, 173, 175, 176, 183, 184, 187
Offset: 1

Views

Author

Clark Kimberling, May 25 2011

Keywords

Comments

See A190803.

Crossrefs

Cf. A190803, A190807, A190849.

Programs

A190851 Integers in (A190808)/2; contains A190808 as a proper subsequence.

Original entry on oeis.org

1, 2, 4, 7, 8, 11, 13, 14, 16, 20, 22, 25, 26, 28, 32, 38, 40, 43, 44, 49, 50, 52, 56, 64, 65, 67, 74, 76, 79, 80, 85, 86, 88, 97, 98, 100, 101, 104, 112, 119, 121, 128, 130, 133, 134, 146, 148, 151, 152, 157, 158, 160, 169, 170, 172, 176, 182, 193, 194, 196, 200, 202, 208, 224, 227, 229, 236, 238, 241, 242, 254, 256, 259, 260, 265, 266
Offset: 1

Views

Author

Clark Kimberling, May 25 2011

Keywords

Comments

See A190803.

Crossrefs

Cf. A190803, A190808, A190852.

Programs

A190852 Integers in (-1+A190808)/3; contains A190808 as a proper subsequence.

Original entry on oeis.org

1, 2, 4, 5, 7, 8, 9, 13, 14, 16, 17, 21, 22, 25, 26, 28, 29, 32, 33, 37, 40, 43, 44, 49, 50, 52, 53, 56, 57, 64, 65, 67, 69, 76, 79, 80, 85, 86, 88, 89, 97, 98, 100, 101, 104, 105, 112, 113, 117, 121, 128, 129, 130, 133, 134, 148, 149, 151, 152, 157, 158, 160, 161, 169, 170, 172, 173, 176, 177, 193, 194, 196, 197, 200, 201, 202, 208, 209
Offset: 1

Views

Author

Clark Kimberling, May 25 2011

Keywords

Comments

See A190803.

Crossrefs

Cf. A190803, A190808, A190851.

Programs

Previous Showing 11-20 of 31 results. Next

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