OFFSET
2,1
COMMENTS
With a different offset: triangle read by rows: t(n, m) = T(n+1, 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, Aug 21 2001
LINKS
T. D. Noe, Rows n = 2..100, flattened
FORMULA
T(n, m) = n*(n+m), n-1 >= m >= 1.
EXAMPLE
The triangle T(n, m) begins:
n\m 1 2 3 4 5 6 7 8 9 10 11 12 13 14 ...
2: 6
3: 12 15
4: 20 24 28
5: 30 35 40 45
6: 42 48 54 60 66
7: 56 63 70 77 84 91
8: 72 80 88 96 104 112 120
9: 90 99 108 117 126 135 144 153
10: 110 120 130 140 150 160 170 180 190
11: 132 143 154 165 176 187 198 209 220 231
12: 156 168 180 192 204 216 228 240 252 264 276
13: 182 195 208 221 234 247 260 273 286 299 312 325
14: 210 224 238 252 266 280 294 308 322 336 350 364 378
15: 240 255 270 285 300 315 330 345 360 375 390 405 420 435
...
[Reformatted and extended by Wolfdieter Lang, Dec 02 2014]
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MATHEMATICA
Flatten[Table[n*(n+m), {n, 2, 10}, {m, n-1}]] (* T. D. Noe, Jun 27 2012 *)
CROSSREFS
KEYWORD
AUTHOR
EXTENSIONS
Edited comment by Wolfdieter Lang, Dec 02 2014
STATUS
approved