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.

Previous Showing 21-27 of 27 results.

A070124 Numbers n such that [A070080(n), A070081(n), A070082(n)] is an acute isosceles integer triangle.

Original entry on oeis.org

1, 2, 3, 4, 6, 7, 9, 10, 11, 12, 15, 16, 18, 19, 22, 23, 24, 27, 28, 31, 34, 35, 38, 39, 40, 43, 46, 47, 48, 51, 54, 55, 58, 63, 64, 65, 68, 71, 72, 73, 76, 81, 84, 85, 88, 93, 94, 95, 98, 103, 107, 108, 109, 112, 117, 120, 121, 124, 129
Offset: 1

Views

Author

Reinhard Zumkeller, May 05 2002

Keywords

Examples

			a(13)=18: [A070080(18), A070081(18), A070082(18)]=[4=4=4], A070085(18)=4^2+4^2-4^2=16>0.

Links

Crossrefs

Cf. A070098, A070126, A070125, A070115, A070118.

A070129 Numbers n such that [A070080(n), A070081(n), A070082(n)] is an obtuse integer triangle with prime side lengths.

Original entry on oeis.org

5, 14, 30, 101, 133, 153, 163, 193, 328, 334, 392, 444, 454, 472, 519, 542, 603, 621, 714, 771, 777, 795, 878, 907, 1005, 1123, 1135, 1508, 1526, 1538, 1694, 1818, 1848, 1858, 1888, 1999, 2023, 2037, 2064, 2066, 2193
Offset: 1

Views

Author

Reinhard Zumkeller, May 05 2002

Keywords

Examples

			a(3)=30: [A070080(30), A070081(30), A070082(30)]=[3,5,7], A070085(30)=3^2+5^2-7^2=9+25-49=-15>0.

Links

Crossrefs

Cf. A070103, A070132, A070135, A070111, A070127.

A070130 Numbers n such that [A070080(n), A070081(n), A070082(n)] is an obtuse scalene integer triangle.

Original entry on oeis.org

8, 13, 20, 21, 25, 29, 30, 36, 37, 41, 42, 44, 49, 50, 56, 57, 59, 62, 66, 67, 69, 74, 75, 77, 78, 79, 80, 86, 87, 89, 96, 97, 99, 100, 101, 102, 105, 110, 111, 113, 115, 122, 123, 125, 126, 127, 128, 130, 131, 138, 139, 141, 143
Offset: 1

Views

Author

Reinhard Zumkeller, May 05 2002

Keywords

Examples

			a(20)=67: [A070080(67), A070081(67), A070082(67)]=[4<7<9], A070085(67)=4^2+7^2-9^2=16+49-81=-16<0.

Links

Crossrefs

Cf. A024156, A070132, A070131, A070112, A070130.

A070133 Numbers n such that [A070080(n), A070081(n), A070082(n)] is an obtuse isosceles integer triangle.

Original entry on oeis.org

5, 14, 26, 32, 52, 61, 82, 91, 104, 118, 133, 146, 163, 182, 202, 219, 242, 246, 266, 291, 314, 342, 347, 372, 404, 432, 437, 467, 472, 504, 542, 547, 577, 582, 619, 625, 663, 709, 714, 751, 757, 801, 807, 853, 858, 907, 913
Offset: 1

Views

Author

Reinhard Zumkeller, May 05 2002

Keywords

Examples

			a(5)=52: [A070080(52), A070081(52), A070082(52)]=[5=5<8], A070085(52)=5^2+5^2-8^2=25+25-64=-14<0.

Links

Crossrefs

Cf. A070106, A070134, A070135, A070115, A070127.

A070121 Numbers n such that [A070080(n), A070081(n), A070082(n)] is an acute scalene integer triangle.

Original entry on oeis.org

33, 45, 53, 60, 70, 83, 90, 92, 106, 114, 119, 132, 134, 142, 148, 162, 165, 168, 175, 181, 183, 197, 200, 203, 204, 218, 221, 224, 237, 240, 245, 247, 261, 264, 267, 268, 282, 290, 293, 296, 309, 312, 316, 317, 319, 333, 341
Offset: 1

Views

Author

Reinhard Zumkeller, May 05 2002

Keywords

Examples

			a(4)=60: [A070080(60), A070081(60), A070082(60)]=[4<7<8], A070085(60)=4^2+7^2-8^2=16+49-64=1>0.

Links

Crossrefs

Cf. A024154, A070122, A070123, A070112, A070118.

A070146 Numbers n such that [A070080(n), A070081(n), A070082(n)] is an acute integer triangle with integer area.

Original entry on oeis.org

39, 269, 375, 587, 862, 972, 1196, 1955, 1988, 2352, 2555, 2796, 3818, 4319, 4406, 5378, 6522, 6808, 6880, 6890, 6921, 7234, 7360, 8193, 9159, 9207, 10272, 14545, 15004, 15061, 15101, 15216, 15237, 15943, 16502
Offset: 1

Views

Author

Reinhard Zumkeller, May 05 2002

Keywords

Examples

			a(1)=39: [A070080(39), A070081(39), A070082(39)] = [5,5,6]: A070085(39)=5^2+5^2-6^2=14>0 and area^2 = s*(s-5)*(s-5)*(s-6) with s=A070083(39)/2=(5+5+6)/2=8, area^2=8*3*3*2=16*9 is an integer square, therefore A070086(39)=area=4*3=12.

Links

Crossrefs

Cf. A070142, A070136, A070147, A070140.

A070147 Numbers k such that [A070080(k), A070081(k), A070082(k)] is an obtuse integer triangle with integer area.

Original entry on oeis.org

52, 252, 368, 372, 561, 659, 839, 957, 1156, 1186, 1204, 1582, 1912, 1920, 1971, 2115, 2713, 2774, 2790, 3251, 3473, 3728, 3746, 4286, 4307, 4313, 4330, 5008, 5272, 5374, 6369, 6389, 6432, 6776, 6881, 7223, 7310, 7341
Offset: 1

Views

Author

Reinhard Zumkeller, May 05 2002

Keywords

Examples

			a(1)=52: [A070080(52), A070081(52), A070082(52)] = [5,5,8]: A070085(52)=5^2+5^2-8^2=-14<0 and area^2 = s*(s-5)*(s-5)*(s-6) with s=A070083(52)/2=(5+5+8)/2=9, area^2=9*4*4*1=16*9 is an integer square, therefore A070086(52)=area=4*3=12.

Links

Crossrefs

Cf. A070142, A070136, A070146, A070141.
Previous Showing 21-27 of 27 results.

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