The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A360218 a(n) is the smallest positive integer which can be represented as the sum of n distinct nonzero square pyramidal numbers in exactly n ways, or -1 if no such integer exists. 2

%I #13 Feb 18 2023 08:07:28

%S 1,5580,2814,1980,1595,1700,2175,2415,2830,3740,4810,5995,7610,9240,

%T 11380,13896,16506,19735,23150,27441,32085,36721,42755,49570,56610,

%U 65135,73165,83021,93835,105671,118255,132545,147546,163516,182155,201040,222371,244280,267856

%N a(n) is the smallest positive integer which can be represented as the sum of n distinct nonzero square pyramidal numbers in exactly n ways, or -1 if no such integer exists.

%H Michael S. Branicky, <a href="/A360218/b360218.txt">Table of n, a(n) for n = 1..80</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SquarePyramidalNumber.html">Square Pyramidal Number</a>

%e For n = 3: 2814 = 14 + 1015 + 1785 = 55 + 650 + 2109 = 140 + 204 + 2470.

%Y Cf. A000330, A350206, A350241, A350397, A360217.

%K nonn

%O 1,2

%A _Ilya Gutkovskiy_, Jan 30 2023

%E a(18)-a(33) from _Michael S. Branicky_, Feb 04 2023

%E a(34) and beyond from _Michael S. Branicky_, Feb 18 2023

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 16 00:16 EDT 2024. Contains 372549 sequences. (Running on oeis4.)