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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A024822 a(n) = least m such that if r and s in {1/1, 1/4, 1/7,..., 1/(3n-2)} satisfy r < s, then r < k/m < s for some integer k.

Original entry on oeis.org

2, 5, 9, 22, 31, 53, 81, 97, 134, 177, 201, 253, 311, 342, 409, 482, 561, 603, 691, 785, 885, 937, 1046, 1161, 1282, 1409, 1475, 1611, 1753, 1901, 2055, 2215, 2297, 2466, 2641, 2822, 3009, 3202, 3301, 3503, 3711, 3925, 4145, 4371, 4486, 4721
Offset: 2

Views

Author

Keywords

Comments

For a guide to related sequences, see A001000. - Clark Kimberling, Aug 07 2012

Crossrefs

Cf. A001000.

Programs

  • Mathematica
    leastSeparator[seq_] := Module[{n = 1},
    Table[While[Or @@ (Ceiling[n #1[[1]]] <
    2 + Floor[n #1[[2]]] &) /@ (Sort[#1, Greater] &) /@
    Partition[Take[seq, k], 2, 1], n++]; n, {k, 2, Length[seq]}]];
    t = Flatten[Table[1/(3 h - 2), {h, 1, 60}]];
    leastSeparator[t]

Extensions

Corrected by Clark Kimberling, Aug 07 2012

A024823 Least m such that if r and s in {1/2, 1/5, 1/8,..., 1/(3n-1)}, satisfy r < s, then r < k/m < s for some integer k.

Original entry on oeis.org

3, 6, 17, 25, 45, 57, 86, 103, 141, 185, 209, 262, 321, 386, 421, 495, 575, 661, 706, 801, 902, 1009, 1122, 1181, 1303, 1431, 1565, 1705, 1777, 1926, 2081, 2242, 2409, 2495, 2671, 2853, 3041, 3235, 3435, 3537, 3746, 3961, 4182, 4409, 4642, 4881, 5003, 5251, 5505
Offset: 2

Views

Author

Keywords

Comments

For a guide to related sequences, see A001000. - Clark Kimberling, Aug 07 2012

Crossrefs

Cf. A001000.

Programs

  • Mathematica
    leastSeparator[seq_] := Module[{n = 1},
    Table[While[Or @@ (Ceiling[n #1[[1]]] <
    2 + Floor[n #1[[2]]] &) /@ (Sort[#1, Greater] &) /@
    Partition[Take[seq, k], 2, 1], n++]; n, {k, 2, Length[seq]}]];
    t = Flatten[Table[1/(3 h - 1), {h, 1, 60}]];
    leastSeparator[t]

A024824 a(n) = least m such that if r and s in {1/3, 1/6, 1/9,..., 1/3n} satisfy r < s, then r < k/m < s for some integer k.

Original entry on oeis.org

4, 7, 19, 28, 49, 61, 91, 127, 148, 193, 244, 271, 331, 397, 469, 508, 589, 676, 769, 817, 919, 1027, 1141, 1261, 1324, 1453, 1588, 1729, 1876, 1951, 2107, 2269, 2437, 2611, 2791, 2884, 3073, 3268, 3469, 3676, 3889, 3997, 4219, 4447, 4681, 4921, 5167, 5419, 5548
Offset: 2

Views

Author

Keywords

Comments

For a guide to related sequences, see A001000. - Clark Kimberling, Aug 07 2012

Crossrefs

Cf. A001000.

Programs

  • Mathematica
    leastSeparator[seq_] := Module[{n = 1},
    Table[While[Or @@ (Ceiling[n #1[[1]]] <
    2 + Floor[n #1[[2]]] &) /@ (Sort[#1, Greater] &) /@
    Partition[Take[seq, k], 2, 1], n++]; n, {k, 2, Length[seq]}]];
    t = Flatten[Table[1/(3 n), {n, 1, 60}]];
    leastSeparator[t]
    (* Peter J. C. Moses, Aug 01 2012 *)

A024825 a(n) = least m such that if r and s in {1/4, 1/8, 1/12,..., 1/4n} satisfy r < s, then r < k/m < s for some integer k.

Original entry on oeis.org

5, 9, 25, 37, 65, 81, 121, 169, 197, 257, 325, 361, 441, 529, 625, 677, 785, 901, 1025, 1089, 1225, 1369, 1521, 1681, 1765, 1937, 2117, 2305, 2501, 2601, 2809, 3025, 3249, 3481, 3721, 3845, 4097, 4357, 4625, 4901, 5185, 5329, 5625, 5929, 6241
Offset: 2

Views

Author

Keywords

Comments

For a guide to related sequences, see A001000. - Clark Kimberling, Aug 07 2012

Crossrefs

Cf. A001000.

Programs

  • Mathematica
    leastSeparator[seq_] := Module[{n = 1},
    Table[While[Or @@ (Ceiling[n #1[[1]]] <
    2 + Floor[n #1[[2]]] &) /@ (Sort[#1, Greater] &) /@
    Partition[Take[seq, k], 2, 1], n++]; n, {k, 2, Length[seq]}]];
    t = Flatten[Table[1/(4 h), {h, 1, 60}]];
    leastSeparator[t]
    (* Peter J. C. Moses, Aug 01 2012 *)

Extensions

Corrected and edited by Clark Kimberling, Aug 07 2012

A024826 Least m such that if r and s in {1/1, 1/3, 1/6,..., 1/C(n+1,2)} satisfy r < s, then r < k/m < s for some integer k.

Original entry on oeis.org

2, 4, 7, 13, 31, 46, 64, 85, 145, 181, 226, 331, 397, 469, 638, 736, 841, 1089, 1225, 1378, 1711, 1901, 2311, 2542, 2784, 3313, 3601, 3901, 4564, 4915, 5685, 6091, 6526, 7441, 7937, 8977, 9538, 10116, 11341, 11989, 13358, 14080, 14821, 16401, 17221, 18964, 19867
Offset: 2

Views

Author

Keywords

Comments

For a guide to related sequences, see A001000. - Clark Kimberling, Aug 07 2012

Crossrefs

Cf. A001000.

Programs

  • Mathematica
    leastSeparator[seq_] := Module[{n = 1},
    Table[While[Or @@ (Ceiling[n #1[[1]]] <
    2 + Floor[n #1[[2]]] &) /@ (Sort[#1, Greater] &) /@
    Partition[Take[seq, k], 2, 1], n++]; n, {k, 2, Length[seq]}]];
    t = Flatten[Table[1/Binomial[h + 1, 2], {h, 1, 50}]]
    leastSeparator[t]

A024827 Least m such that if r and s in {1/1, 1/4, 1/9,..., 1/n^2} satisfy r < s, then r < k/m < s for some integer k.

Original entry on oeis.org

2, 5, 10, 19, 33, 76, 109, 148, 197, 325, 406, 501, 727, 865, 1015, 1373, 1576, 1801, 2313, 2602, 3250, 3611, 4001, 4852, 5325, 5820, 6913, 7501, 8789, 9478, 10207, 11775, 12616, 14416, 15377, 16385, 18514, 19653, 22051, 23329, 24643, 27437, 28900, 32001, 33621
Offset: 2

Views

Author

Keywords

Comments

For a guide to related sequences, see A001000. - Clark Kimberling, Aug 07 2012

Crossrefs

Cf. A001000.

Programs

  • Mathematica
    leastSeparator[seq_] := Module[{n = 1},
    Table[While[Or @@ (Ceiling[n #1[[1]]] <
    2 + Floor[n #1[[2]]] &) /@ (Sort[#1, Greater] &) /@
    Partition[Take[seq, k], 2, 1], n++]; n, {k, 2, Length
    [seq]}]];
    t = Flatten[Table[1/h^2, {h, 1, 60}]]
    leastSeparator[t]

A024828 a(n) = least m such that if r and s in {h/(1 + h^2): h = 1,2,...,n} satisfy r < s, then r < k/m < s for some integer k.

Original entry on oeis.org

7, 9, 11, 14, 18, 27, 32, 44, 58, 66, 83, 102, 112, 134, 158, 184, 198, 227, 258, 291, 308, 344, 382, 422, 464, 486, 531, 578, 627, 678, 704, 758, 814, 872, 932, 994, 1026, 1091, 1158, 1227, 1298, 1371, 1408, 1484, 1562, 1642, 1724, 1808, 1894, 1938, 2027, 2118, 2211, 2306
Offset: 2

Views

Author

Keywords

Comments

For a guide to related sequences, see A001000. - Clark Kimberling, Aug 07 2012

Crossrefs

Cf. A001000.

Programs

  • Mathematica
    leastSeparator[seq_] := Module[{n = 1},
    Table[While[Or @@ (Ceiling[n #1[[1]]] <
    2 + Floor[n #1[[2]]] &) /@ (Sort[#1, Greater] &) /@
    Partition[Take[seq, k], 2, 1], n++]; n, {k, 2, Length[seq]}]];
    t = Flatten[Table[h/(1 + h^2), {h, 1, 60}]]
    leastSeparator[t]
    (* Peter J. C. Moses, Aug 01 2012 *)

A024829 a(n) = least m such that if r and s in {F(2*h-1)/F(2*h): h = 1,2,...,n} satisfy r < s, then r < k/m < s for some integer k, where F = A000045 (Fibonacci numbers).

Original entry on oeis.org

4, 11, 29, 173, 1063, 7074, 47753, 325961, 2228269, 15262701, 104577551, 716721983, 4912208209
Offset: 2

Views

Author

Keywords

Comments

For a guide to related sequences, see A001000. - Clark Kimberling, Aug 07 2012

Crossrefs

Programs

  • Mathematica
    leastSeparator[seq_] := Module[{n = 1},
    Table[While[Or @@ (Ceiling[n #1[[1]]] <
    2 + Floor[n #1[[2]]] &) /@ (Sort[#1, Greater] &) /@
    Partition[Take[seq, k], 2, 1], n++]; n, {k, 2, Length[seq]}]];
    t = Table[N[Fibonacci[2 h - 1]/Fibonacci[2 h]], {h, 1, 10}]
    t1 = leastSeparator[t]
    (* Peter J. C. Moses, Aug 01 2012 *)

Extensions

Corrected by Clark Kimberling, Aug 07 2012
a(11)-a(14) from Sean A. Irvine, Jul 25 2019

A024830 a(n) = least m such that if r and s in {F(2*h)/F(2*h+1): h = 1,2,...,n} satisfy r < s, then r < k/m < s for some integer k, where F = A000045 (Fibonacci numbers).

Original entry on oeis.org

7, 18, 73, 424, 2741, 18389, 124799, 851937, 5831634, 39952039, 273777171, 1876334786, 12860231668
Offset: 2

Views

Author

Keywords

Comments

See A001000 for a guide to related sequences. - Clark Kimberling, Aug 07 2012

Crossrefs

Programs

  • Mathematica
    (* For a guide to related sequences, see A001000. *)
    leastSeparator[seq_] := Module[{n = 1},
    Table[While[Or @@ (Ceiling[n #1[[1]]] <
    2 + Floor[n #1[[2]]] &) /@ (Sort[#1, Greater] &) /@
    Partition[Take[seq, k], 2, 1], n++]; n, {k, 2, Length[seq]}]];
    t = Table[N[Fibonacci[2 h]/Fibonacci[2 h + 1]], {h, 1, 10}];
    t1 = leastSeparator[t]
    (* Peter J. C. Moses, Aug 01 2012 *)

Extensions

Extended by Clark Kimberling, Aug 07 2012
a(11)-a(14) from Sean A. Irvine, Jul 25 2019

A024833 a(n) = least m such that if r and s in {1/1, 1/2, 1/3, ..., 1/n} satisfy r < s, then r < k/m < (k+1)/m < s for some integer k.

Original entry on oeis.org

5, 11, 19, 29, 41, 61, 79, 106, 129, 163, 191, 232, 265, 313, 365, 407, 466, 529, 579, 649, 723, 781, 862, 947, 1013, 1105, 1201, 1301, 1379, 1486, 1597, 1712, 1801, 1923, 2049, 2179, 2279, 2416, 2557, 2702, 2813, 2965, 3121, 3281, 3445, 3571, 3742, 3917, 4096
Offset: 2

Views

Author

Keywords

Comments

For a guide to related sequences, see A001000. - Peter J. C. Moses, Aug 08 2012

Examples

			Using the terminology introduced at A001000, the 2nd separator of the set {1/3, 1/2, 1} is a(3) = 11, since 1/3 < 4/11 < 5/11 < 1/2 < 6/11 < 7/11 < 1 and 11 is the least m for which 1/3, 1/2, 1 are thus separated using numbers k/m. - _Clark Kimberling_, Aug 08 2012
		

Crossrefs

Programs

  • Mathematica
    leastSeparatorS[seq_, s_] := Module[{n = 1},
    Table[While[Or @@ (Ceiling[n #1[[1]]] <
    s + 1 + Floor[n #1[[2]]] &) /@ (Sort[#1, Greater] &) /@
    Partition[Take[seq, k], 2, 1], n++]; n, {k, 2, Length[seq]}]];
    t = Map[leastSeparatorS[1/Range[50], #] &, Range[5]];
    TableForm[t]
    t[[2]] (* Clark Kimberling, Aug 08 2012 *)
Previous Showing 21-30 of 36 results. Next