A132127 a(n) = (n^3 + 3*n - 2)/2.
1, 6, 17, 37, 69, 116, 181, 267, 377, 514, 681, 881, 1117, 1392, 1709, 2071, 2481, 2942, 3457, 4029, 4661, 5356, 6117, 6947, 7849, 8826, 9881, 11017, 12237, 13544, 14941, 16431, 18017, 19702, 21489, 23381, 25381, 27492, 29717, 32059, 34521, 37106, 39817, 42657, 45629
Offset: 1
Examples
From _Wesley Ivan Hurt_, May 18 2021: (Start)
Sum of the numbers in the top row and 1st column.
[1 2 3 4 5]
[1 2 3 4] [6 7 8 9 10]
[1 2 3] [5 6 7 8] [11 12 13 14 15]
[1 2] [4 5 6] [9 10 11 12] [16 17 18 19 20]
[1] [3 4] [7 8 9] [13 14 15 16] [21 22 23 24 25]
------------------------------------------------------------------------
n 1 2 3 4 5
------------------------------------------------------------------------
a(n) 1 6 17 37 69
------------------------------------------------------------------------
(End)
Links
- Andrew Howroyd, Table of n, a(n) for n = 1..1000
Programs
-
Mathematica
Table[n*(n^2 + 3)/2 - 1, {n, 80}] (* Wesley Ivan Hurt, May 18 2021 *) -
PARI
a(n) = (n^3 + 3*n - 2)/2; \\ Andrew Howroyd, Apr 17 2021
Formula
a(n) = n*(n^2 + 3)/2 - 1.
Extensions
Edited and terms a(13) and beyond from Andrew Howroyd, Apr 17 2021
Comments