|
| |
|
|
A129994
|
|
Triangle read by rows: 2*A007318 - I.
|
|
1
|
|
|
|
1, 2, 1, 2, 4, 1, 2, 6, 6, 1, 2, 8, 12, 8, 1, 2, 10, 20, 20, 10, 1, 2, 12, 30, 40, 30, 12, 1, 2, 14, 42, 70, 70, 42, 14, 1, 2, 16, 56, 112, 140, 112, 56, 16, 1, 2, 18, 72, 168, 252, 252, 168, 72, 18, 1
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
0,2
|
|
|
COMMENTS
|
Row sums = (1, 3, 7, 15, 31, ...).
|
|
|
LINKS
|
Table of n, a(n) for n=0..54.
|
|
|
FORMULA
|
Let Pascal's triangle A007318 = P, then this is 2*P - I, I = Identity matrix.
|
|
|
EXAMPLE
|
First few rows of the triangle are:
1;
2, 1;
2, 4, 1;
2, 6, 6, 1;
2, 8, 12, 8, 1;
2, 10, 20, 20, 10, 1;
2, 12, 30, 40, 30, 12, 1;
...
|
|
|
MATHEMATICA
|
Table[2 Binomial[n, k] - Boole[k == n], {n, 0, 9}, {k, 0, n}] // Flatten (* Michael De Vlieger, Nov 02 2017 *)
|
|
|
CROSSREFS
|
Cf. A007318.
Sequence in context: A210215 A203647 A114791 * A208755 A226441 A080246
Adjacent sequences: A129991 A129992 A129993 * A129995 A129996 A129997
|
|
|
KEYWORD
|
nonn,tabl
|
|
|
AUTHOR
|
Gary W. Adamson, Jun 15 2007
|
|
|
EXTENSIONS
|
Name corrected by Peter Bala, Nov 02 2017
|
|
|
STATUS
|
approved
|
| |
|
|
