|
Search: id:A079297
|
|
|
| A079297 |
|
Triangle read by rows: the k-th column is an arithmetic progression with difference 2k-1, and the top entry is the hexagonal number k*(2*k-1) (A000384). |
|
+0
1
|
|
| 1, 2, 6, 3, 9, 15, 4, 12, 20, 28, 5, 15, 25, 35, 45, 6, 18, 30, 42, 54, 66, 7, 21, 35, 49, 63, 77, 91, 8, 24, 40, 56, 72, 88, 104, 120, 9, 27, 45, 63, 81, 99, 117, 135, 153, 10, 30, 50, 70, 90, 110, 130, 150, 170, 190, 11, 33, 55, 77, 99, 121, 143, 165, 187, 209, 231, 12
(list; table; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
The n-th row consists of the odd multiples of n from n*1 to n*(2n-1).
|
|
REFERENCES
|
R. Honsberger, Ingenuity in Math., Random House, 1970, p. 88.
|
|
FORMULA
|
n-th row adds to n^3.
a(n, k) = n(2k-1) for 1<=k<=n.
|
|
EXAMPLE
|
Triangle begins:
1
2 6
3 9 15
4 12 20 28
5 15 25 35 45
6 18 30 42 54 66
|
|
MATHEMATICA
|
Flatten[Table[n(2k-1), {n, 1, 12}, {k, 1, n}]]
|
|
CROSSREFS
|
Adjacent sequences: A079294 A079295 A079296 this_sequence A079298 A079299 A079300
Sequence in context: A133917 A078340 A136190 this_sequence A143219 A109465 A090705
|
|
KEYWORD
|
nonn,tabl,easy
|
|
AUTHOR
|
njas, Mar 04 2003
|
|
EXTENSIONS
|
More terms from Dean Hickerson, Apr 06, 2003
|
|
|
Search completed in 0.002 seconds
|
