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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A179406 Record minima of the positive distance d between the fifth power of a positive integer x and the square of an integer y such that d = x^5 - y^2 (x != k^2 and y != k^5).

Original entry on oeis.org

7, 19, 60, 341, 47776, 70378, 78846, 115775, 220898, 780231, 2242100, 11889984, 26914479, 50406928, 77146256, 80117392, 284679759, 595974650, 2071791247, 7825152599, 67944824923, 742629277177, 1709838230002, 2676465117663
Offset: 1

Views

Author

Artur Jasinski, Jul 13 2010

Keywords

Comments

Distance d is equal to 0 when x = k^2 and y = k^5.
For x values see A179407.
For y values see A179408.
Conjecture (from Artur Jasinski): For any positive number x >= A179407(n), the distance d between the fifth power of x and the square of any y (such that x != k^2 and y != k^5) can't be less than A179406(n).

Crossrefs

Programs

  • Mathematica
    max = 1000; vecd = Table[10^100, {n, 1, max}]; vecx = Table[10^100, {n, 1, max}]; vecy = Table[10^100, {n, 1, max}]; len = 1; Do[m = Floor[(n^5)^(1/2)]; k = n^5 - m^2; If[k != 0, ile = 0; Do[If[vecd[[z]] < k, ile = ile + 1], {z, 1, len}]; len = ile + 1; vecd[[len]] = k; vecx[[len]] = n; vecy[[len]] = m], {n, 1, 96001}]; dd = {}; xx = {}; yy = {}; Do[AppendTo[dd, vecd[[n]]]; AppendTo[xx, vecx[[n]]]; AppendTo[yy, vecy[[n]]], {n, 1, len}]; dd

A179798 Record minima of the positive distance d between the 11th power of a positive integer x and the square of an integer y such that d = x^13 - y^2 (x <> k^2 and y <> k^13).

Original entry on oeis.org

92, 1679, 39281, 89927, 296863, 1530322, 12056004, 55972895, 67903894, 102383343, 641211875, 5148097536, 13764973788, 19839459725, 87957606400, 113794567580, 126889914716, 146745583311, 880304597278, 1154049177924
Offset: 1

Views

Author

Artur Jasinski, Jul 27 2010

Keywords

Comments

Distance d is equal to 0 when x = k^2 and y = k^13.
For x values see A179799.
For x values see A179800.
Conjecture (Artur Jasinski):
For any positive number x >= A179799(n), the distance d between the eleventh power of x and the square of any y (such that x <> k^2 and y <> k^13) can't be less than A179798(n).

Crossrefs

Programs

  • Mathematica
    d = 13; max = 1000; vecd = Table[10^100, {n, 1, max}]; vecx = Table[10^100, {n, 1, max}]; vecy = Table[10^100, {n, 1, max}]; len = 1; Do[m = Floor[(n^d)^(1/2)]; k = n^d - m^2; If[k != 0, ile = 0; Do[If[vecd[[z]] < k, ile = ile + 1], {z, 1, len}]; len = ile + 1; vecd[[len]] = k; vecx[[len]] = n; vecy[[len]] = m], {n, 1, 10000000}]; dd = {}; xx = {}; yy = {}; Do[AppendTo[dd, vecd[[n]]]; AppendTo[xx, vecx[[n]]]; AppendTo[yy, vecy[[n]]], {n, 1, len}]; dd

A179799 Values x for records of minima of the positive distance d between an 11th power of a positive integer x and a square of an integer y such that d = x^13 - y^2 (x<>k^2 and y<>k^13).

Original entry on oeis.org

2, 3, 5, 6, 8, 11, 13, 14, 23, 24, 35, 40, 42, 45, 50, 54, 62, 70, 79, 85, 88, 89, 142, 152, 220, 345, 353, 364, 412, 416, 455, 627, 734, 743, 911, 921, 1068, 1095, 1294, 1894, 2398, 2719, 2887, 3015, 3623, 3814, 5837, 6226, 8603, 8669, 8971, 9987, 12683
Offset: 1

Views

Author

Artur Jasinski, Jul 27 2010

Keywords

Comments

Distance d = 0 when x = k^2 and y = k^13.
For d values see A179798.
For y values see A179800.
Conjecture: For any positive number x >= A179799(n) the distance d between the 11th power of x and the square of any y (such that x<>k^2 and y<>k^13) can't be less than A179798(n).

Crossrefs

Programs

  • Mathematica
    d = 13; max = 1000; vecd = Table[10^100, {n, 1, max}]; vecx = Table[10^100, {n, 1, max}]; vecy = Table[10^100, {n, 1, max}]; len = 1; Do[m = Floor[(n^d)^(1/2)]; k = n^d - m^2; If[k != 0, ile = 0; Do[If[vecd[[z]] < k, ile = ile + 1], {z, 1, len}]; len = ile + 1; vecd[[len]] = k; vecx[[len]] = n; vecy[[len]] = m], {n, 1, 10000000}]; dd = {}; xx = {}; yy = {}; Do[AppendTo[dd, vecd[[n]]]; AppendTo[xx, vecx[[n]]]; AppendTo[yy, vecy[[n]]], {n, 1, len}]; xx

A179800 Values y for record minima of the positive distance d between the thirteenth power of a positive integer x and the square of an integer y such that d = x^13 - y^2 (x <> k^2 and y <> k^13).

Original entry on oeis.org

90, 1262, 34938, 114283, 741455, 5875603, 17403307, 28172943, 709955183, 936209559, 10875326100, 25905378592, 35572991418, 55703353220, 110485434560, 182204642678, 447245502234, 984322154617, 2160608565081, 3477146726351
Offset: 1

Views

Author

Artur Jasinski, Jul 27 2010

Keywords

Comments

Distance d is equal to 0 when x = k^2 and y = k^13.
For d values see A179798.
For x values see A179799.
Conjecture: For any positive number x >= A179799(n), the distance d between the 13th power of x and the square of any y (such that x <> k^2 and y <> k^13) can't be less than A179798(n).

Crossrefs

Programs

  • Mathematica
    d = 13; max = 1000; vecd = Table[10^100, {n, 1, max}]; vecx = Table[10^100, {n, 1, max}]; vecy = Table[10^100, {n, 1, max}]; len = 1; Do[m = Floor[(n^d)^(1/2)]; k = n^d - m^2; If[k != 0, ile = 0; Do[If[vecd[[z]] < k, ile = ile + 1], {z, 1, len}]; len = ile + 1; vecd[[len]] = k; vecx[[len]] = n; vecy[[len]] = m], {n, 1, 10000000}]; dd = {}; xx = {}; yy = {}; Do[AppendTo[dd, vecd[[n]]]; AppendTo[xx, vecx[[n]]]; AppendTo[yy, vecy[[n]]], {n, 1, len}]; yy

A179812 Record minima of the positive distance d between the fifteenth power of a positive integer x and the square of an integer y such that d = x^15 - y^2 (x <> k^2 and y <> k^15).

Original entry on oeis.org

7, 7538, 283261, 494576, 4235622, 7135951, 38053824, 55905695, 185380312, 1208691743, 3263221507, 14034746735, 14732727599, 24211719874, 68491624661, 136264246246, 5337970328375, 6845918569200, 15505738619231, 30037885135088
Offset: 1

Views

Author

Artur Jasinski, Jul 28 2010

Keywords

Comments

Distance d is equal to 0 when x = k^2 and y = k^15.
For x values see A179813.
For y values see A179814.
Conjecture: For any positive number x >= A179813(n), the distance d between the fifteenth power of x and the square of any y (such that x <> k^2 and y <> k^15) can't be less than A179812(n).

Crossrefs

Programs

  • Mathematica
    d = 15; max = 1000; vecd = Table[10^100, {n, 1, max}]; vecx = Table[10^100, {n, 1, max}]; vecy = Table[10^100, {n, 1, max}]; len = 1; Do[m = Floor[(n^d)^(1/2)]; k = n^d - m^2; If[k != 0, ile = 0; Do[If[vecd[[z]] < k, ile = ile + 1], {z, 1, len}]; len = ile + 1; vecd[[len]] = k; vecx[[len]] = n; vecy[[len]] = m], {n, 1, 10000000}]; dd = {}; xx = {}; yy = {}; Do[AppendTo[dd, vecd[[n]]]; AppendTo[xx, vecx[[n]]]; AppendTo[yy, vecy[[n]]], {n, 1, len}]; dd

A179813 Values x for record minima of the positive distance d between the fifteenth power of a positive integer x and the square of an integer y such that d = x^15 - y^2 (x <> k^2 and y <> k^15).

Original entry on oeis.org

2, 3, 5, 6, 7, 8, 10, 11, 17, 18, 23, 24, 27, 35, 45, 55, 56, 76, 78, 84, 111, 114, 115, 117, 118, 139, 164, 172, 175, 176, 179, 183, 188, 190, 193, 305, 316, 377, 395, 461, 466, 483, 485, 654, 747, 868, 877, 931, 1045, 1434, 1822, 2199, 2645, 2754, 3171, 3961
Offset: 1

Views

Author

Artur Jasinski, Jul 28 2010

Keywords

Comments

Distance d is equal to 0 when x = k^2 and y = k^15.
For x values see A179813.
For y values see A179814.
Conjecture: For any positive number x >= A179813(n), the distance d between the fifteenth power of x and the square of any y (such that x <> k^2 and y <> k^15) can't be less than A179812(n).

Crossrefs

Programs

  • Mathematica
    d = 15; max = 1000; vecd = Table[10^100, {n, 1, max}]; vecx = Table[10^100, {n, 1, max}]; vecy = Table[10^100, {n, 1, max}]; len = 1; Do[m = Floor[(n^d)^(1/2)]; k = n^d - m^2; If[k != 0, ile = 0; Do[If[vecd[[z]] < k, ile = ile + 1], {z, 1, len}]; len = ile + 1; vecd[[len]] = k; vecx[[len]] = n; vecy[[len]] = m], {n, 1, 10000000}]; dd = {}; xx = {}; yy = {}; Do[AppendTo[dd, vecd[[n]]]; AppendTo[xx, vecx[[n]]]; AppendTo[yy, vecy[[n]]], {n, 1, len}]; xx

A179814 Values y for record minima of the positive distance d between the fifteenth power of a positive integer x and the square of an integer y such that d = x^15 - y^2 (x <> k^2 and y <> k^15).

Original entry on oeis.org

181, 3787, 174692, 685700, 2178889, 5931641, 31622776, 64631634, 1691869691, 2597429617, 16328969210, 22469029417, 54353589638, 380636413501, 2506650894908, 11290681881873, 12924394402851, 127673846293724
Offset: 1

Views

Author

Artur Jasinski, Jul 28 2010

Keywords

Comments

Distance d is equal to 0 when x = k^2 and y = k^15.
For d values see A179812.
For x values see A179813.
Conjecture: For any positive number x >= A179813(n), the distance d between the fifteenth power of x and the square of any y (such that x <> k^2 and y <> k^15) can't be less than A179812(n).

Crossrefs

Programs

  • Mathematica
    d = 15; max = 1000; vecd = Table[10^100, {n, 1, max}]; vecx = Table[10^100, {n, 1, max}]; vecy = Table[10^100, {n, 1, max}]; len = 1; Do[m = Floor[(n^d)^(1/2)]; k = n^d - m^2; If[k != 0, ile = 0; Do[If[vecd[[z]] < k, ile = ile + 1], {z, 1, len}]; len = ile + 1; vecd[[len]] = k; vecx[[len]] = n; vecy[[len]] = m], {n, 1, 10000000}]; dd = {}; xx = {}; yy = {}; Do[AppendTo[dd, vecd[[n]]]; AppendTo[xx, vecx[[n]]]; AppendTo[yy, vecy[[n]]], {n, 1, len}]; yy

A179447 Smallest values d such that the equation d =x^5-y^2 has exactly n distinct nonnegative integer solutions.

Original entry on oeis.org

2, 1, 7, 1044976, 11331151
Offset: 0

Views

Author

Artur Jasinski, Jul 14 2010

Keywords

Comments

a(0)=2 because no integer solutions x^5-y^2 = 2;
a(1)=1 because 1=1^5-0^2;
a(2)=7 because 7=2^5-5^2 and 7=8^5-181^2;
a(3)=1044976 because 1044976=16^5-60^2 and 1044976=20^5-1468^2 and 1044976=41^5-10715^2;
a(4)=11331151 because 11331151=35^5-6418^2 and 11331151=40^5-9543^2 and 11331151=56^5-23225^2 and 11331151=386^5-2927305^2.

Crossrefs

A180139 a(n)=A179387(n)+1.

Original entry on oeis.org

4, 6, 33, 36, 38, 64, 66, 137, 569, 5216, 367807, 939788, 6369040, 7885439, 9536130, 140292678, 184151167, 890838664, 912903446, 3171881613
Offset: 1

Views

Author

Artur Jasinski, Aug 12 2010

Keywords

Comments

Theorem (*Artur Jasinski*):
For any positive number x >= A180139(n) distance between cube of x and square of any y (such that x<>n^2 and y<>n^3) can't be less than A179386(n+1).
Proof: Because number of integral points of each Mordell elliptic curve of the form x^3-y^2 = k is finite and completely computable, such x can't exist.
If x=n^2 and y=n^3 distance d=0.
For d values see A179386.
For y values see A179388.

Examples

			For numbers x from 4 to infinity distance can't be less than 4.
For numbers x from 6 to infinity distance can't be less than 7.
For numbers x from 33 to infinity distance can't be less than 26.
For numbers x from 36 to infinity distance can't be less than 28.
For numbers x from 38 to infinity distance can't be less than 49.
For numbers x from 66 to infinity distance can't be less than 60.
For numbers x from 137 to infinity distance can't be less than 63.
For numbers x from 569 to infinity distance can't be less than 174.
For numbers x from 5216 to infinity distance can't be less than 207.
For numbers x from 367807 to infinity distance can't be less than 307.
		

Crossrefs

A179448 Numbers d such that the equation d =x^5-y^2 has more than 2 distinct nonnegative integer solutions.

Original entry on oeis.org

1044976, 1541468, 11331151, 15579791, 16410368, 33543196, 46539324, 72697500, 302272796, 528292607
Offset: 1

Views

Author

Artur Jasinski, Jul 14 2010

Keywords

Examples

			a(1)=1044976 because 1044976=16^5-60^2 and 1044976=20^5-1468^2 and 1044976=41^5-10715^2;
a(3)=11331151 because 11331151=35^5-6418^2 and 11331151=40^5-9543^2 and 11331151=56^5-23225^2 and 11331151=386^5-2927305^2.
		

Crossrefs

Previous Showing 21-30 of 32 results. Next