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 1-4 of 4 results.

A350397 a(n) is the smallest number which can be represented as the sum of n distinct nonzero n-gonal pyramidal numbers in exactly n ways, or -1 if no such number exists.

Original entry on oeis.org

305, 1980, 1900, 3321, 5256, 8310, 12516, 17108, 24832, 34249, 42381, 61697, 78766, 106956, 132994, 170325, 203415, 266595, 322943, 393828, 475520, 569416, 695799, 823447, 958300, 1149125, 1313545, 1565055, 1802736, 2088119, 2376250, 2748270, 3135195, 3548876
Offset: 3

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Author

Ilya Gutkovskiy, Dec 29 2021

Keywords

Examples

			For n = 3: 305 = 1 + 84 + 220 = 20 + 120 + 165 = 56 + 84 + 165.
		

Crossrefs

Extensions

a(10)-a(22) from Michael S. Branicky, Dec 29 2021
a(23)-a(36) from Martin Ehrenstein, Jan 14 2022

A350207 a(n) is the smallest positive integer which can be represented as the sum of distinct nonzero n-gonal numbers in exactly n ways, or 0 if no such integer exists.

Original entry on oeis.org

25, 65, 144, 305, 456, 622, 731, 1006, 1434, 1499, 1711, 1806, 2446, 2742, 3001, 3051, 3544, 3699, 3962, 4345, 5362, 5039, 5756, 5712, 6251, 6655, 7399, 7698, 7591, 8304, 8673, 9241, 9362, 9299, 10312, 10606, 11121, 10736, 12113, 12737, 12934
Offset: 3

Views

Author

Ilya Gutkovskiy, Dec 19 2021

Keywords

Crossrefs

A350209 a(n) is the smallest positive integer which can be represented as the sum of distinct centered n-gonal numbers in exactly n ways, or 0 if no such integer exists.

Original entry on oeis.org

65, 151, 330, 316, 515, 645, 888, 824, 1017, 1348, 1474, 1614, 1655, 2006, 2233, 2255, 2779, 2805, 2882, 2865, 3364, 3653, 3930, 4035, 4325, 4765, 4675, 5016, 4904, 5446, 5913, 5990, 6061, 6954, 6850, 7681, 8313, 7846, 7591, 9035, 8736
Offset: 3

Views

Author

Ilya Gutkovskiy, Dec 19 2021

Keywords

Crossrefs

A359321 a(n) is the smallest n-gonal pyramidal number which can be represented as the sum of n distinct nonzero n-gonal pyramidal numbers in exactly n ways, or -1 if none exists.

Original entry on oeis.org

2300, 6201, 8125, 6391
Offset: 3

Views

Author

Ilya Gutkovskiy, Dec 25 2022

Keywords

Examples

			For n = 3: 2300 = 1 + 969 + 1330 = 56 + 220 + 2024 = 165 + 364 + 1771.
For n = 4: 6201 = 1 + 91 + 1785 + 4324 = 1 + 285 + 1015 + 4900 = 30 + 140 + 506 + 5525 = 91 + 819 + 1496 + 3795.
		

Crossrefs

Showing 1-4 of 4 results.