login
A276189
Triangle read by rows: T(n,k) = 2*(6*k^2 + 1)*(n + 1 - k) for 0 < k <= n; for k = 0, T(n,0) = n + 1.
2
1, 2, 14, 3, 28, 50, 4, 42, 100, 110, 5, 56, 150, 220, 194, 6, 70, 200, 330, 388, 302, 7, 84, 250, 440, 582, 604, 434, 8, 98, 300, 550, 776, 906, 868, 590, 9, 112, 350, 660, 970, 1208, 1302, 1180, 770, 10, 126, 400, 770, 1164, 1510, 1736, 1770, 1540, 974, 11, 140, 450, 880, 1358, 1812, 2170, 2360, 2310, 1948, 1202
OFFSET
0,2
COMMENTS
The row sums of the triangle provide the positive terms of A000583.
Similar triangles can be generated by the formula P(n,k,m) = (Q(k+1,m)-Q(k,m))*(n+1-k), where Q(i,r) = i^r-(i-1)^r, 0 < k <= n, and P(n,0,m) = n+1. T(n,k) is the case m=4, that is T(n,k) = P(n,k,4).
LINKS
Michael De Vlieger, Table of n, a(n) for n = 0..11475 (rows 0 <= n <= 150, flattened)
FORMULA
T(n,n-h) = (h+1)*A005914(n-h) for 0 <= h <= n. Therefore, the main diagonal of the triangle is A005914.
Sum_{k=0..n} T(n,k) = T(n,0)^4 = A000583(n+1).
EXAMPLE
Triangle starts:
----------------------------------------------
n \ k | 0 1 2 3 4 5 6 7
----------------------------------------------
0 | 1;
1 | 2, 14;
2 | 3, 28, 50;
3 | 4, 42, 100, 110;
4 | 5, 56, 150, 220, 194;
5 | 6, 70, 200, 330, 388, 302;
6 | 7, 84, 250, 440, 582, 604, 434;
7 | 8, 98, 300, 550, 776, 906, 868, 590;
...
MATHEMATICA
Table[If[k == 0, n + 1, 2 (6 k^2 + 1) (n + 1 - k)], {n, 0, 9}, {k, 0, n}] // Flatten (* Michael De Vlieger, Aug 29 2016 *)
PROG
(Magma) [IsZero(k) select n+1 else 2*(6*k^2+1)*(n+1-k): k in [0..n], n in [0..10]];
(Magma) /* As triangle (see the second comment): */ m:=4; Q:=func<i, r | i^r-(i-1)^r>; P:=func<n, k, m | IsZero(k) select n+1 else (Q(k+1, m)-Q(k, m))*(n+1-k)>; [[P(n, k, m): k in [0..n]]: n in [0..10]];
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Stefano Maruelli, Aug 24 2016
EXTENSIONS
Corrected, rewritten and extended by Bruno Berselli, Aug 31 2016
a(40) ff. corrected by Georg Fischer, Nov 08 2021
STATUS
approved