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 1-2 of 2 results.

A360777 a(n) is the index of the least n-gonal number that is the sum of two or more consecutive nonzero n-gonal numbers in more than one way, or -1 if no such number exists.

Original entry on oeis.org

9, 160, 143, 2679, 19933, 115248, 45, 1995
Offset: 2

Views

Author

Ilya Gutkovskiy, Feb 20 2023

Keywords

Comments

a(10)>2000000, a(11)=24375, a(12)=133307113, a(13)=6715891, a(16)=189308, a(20)=9009. - Sean A. Irvine, Mar 24 2023

Links

Crossrefs

Cf. A057145, A360762.

A360836 a(n) is the least n-gonal pyramidal number that is the sum of two or more consecutive nonzero n-gonal pyramidal numbers in more than one way.

Original entry on oeis.org

12880, 18896570
Offset: 2

Views

Author

Ilya Gutkovskiy, Feb 23 2023

Keywords

Comments

a(4) > 10^19 if it exists. - Michael S. Branicky, Feb 23 2023

Examples

			For n = 2: 12880 = 91 + ... + 903 = 300 + ... + 990.
For n = 3: 18896570 = 708561 + ... + 1021384 = 2604125 + ... + 2796160.

Links

Crossrefs

Cf. A080851, A360762.
Showing 1-2 of 2 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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