|
Search: id:A001283
|
|
|
| A001283 |
|
Triangle read by rows, in which row m consists of m(m+1), ..., m(2m-1). |
|
+0
6
|
|
| 6, 12, 15, 20, 24, 28, 30, 35, 40, 45, 42, 48, 54, 60, 66, 56, 63, 70, 77, 84, 91, 72, 80, 88, 96, 104, 112, 120, 90, 99, 108, 117, 126, 135, 144, 153, 110, 120, 130, 140, 150, 160, 170, 180, 190, 132, 143, 154, 165, 176, 187, 198, 209, 220, 231, 156, 168, 180
(list; table; graph; listen)
|
|
|
OFFSET
|
2,1
|
|
|
COMMENT
|
With a different offset: triangle read by rows: T(n,m) = (n+1)(n+m+1) = radius of C-excircle of Pythagorean triangle with sides a=(n+1)^2-m^2, b=2*(n+1)*m and c=(n+1)^2+m^2. - Floor van Lamoen (fvlamoen(AT)hotmail.com), Aug 21 2001
|
|
EXAMPLE
|
6; 12,15; 20,24,28; 30,35,40,45; 42,48,54,60,66; ...
|
|
CROSSREFS
|
Cf. A003991, A063929, A063930.
Row sums are in A085788. Central column is A033581.
Sequence in context: A129494 A001284 A063931 this_sequence A106430 A106420 A081535
Adjacent sequences: A001280 A001281 A001282 this_sequence A001284 A001285 A001286
|
|
KEYWORD
|
nonn,easy,tabl
|
|
AUTHOR
|
N. J. A. Sloane (njas(AT)research.att.com).
|
|
|
Search completed in 0.002 seconds
|
