A217793 Erdős-Turán Golomb rulers, triangle read by rows.

0, 7, 13, 0, 11, 24, 34, 41, 0, 15, 32, 44, 58, 74, 85, 0, 23, 48, 75, 93, 113, 135, 159, 185, 202, 221, 0, 27, 56, 87, 107, 142, 166, 192, 220, 237, 269, 290, 313, 0, 35, 72, 111, 152, 178, 206, 253, 285, 319, 355, 376, 416, 458, 485, 514, 545, 0, 39, 80

Offset: 1

Author

Reinhard Zumkeller, Mar 25 2013

Keywords

• nonn
• tabf

Examples

			First rows:
.  1  0,7,13
.  2  0,11,24,34,41
.  3  0,15,32,44,58,74,85
.  4  0,23,48,75,93,113,135,159,185,202,221
.  5  0,27,56,87,107,142,166,192,220,237,269,290,313
.  6  0,35,72,111,152,178,206,253,285,319,355,376,416,458,485,514,545 .
		

Links

• Reinhard Zumkeller, Rows n = 1..60 of triangle, flattened
• P. Erdős and P. Turán, On a problem of Sidon in additive number theory, and on some related problems, J. Lond. Math. Soc. 16 (1941), 212-215.
• Eric Weisstein's World of Mathematics, Golomb Ruler.
• Wikipedia, Golomb ruler
• Index entries for sequences related to Golomb rulers

Crossrefs

Cf. A065091 (row lengths).

Programs

Haskell

a217793 n k = a217793_tabf !! (n-1) !! k
a217793_row n = a217793_tabf !! (n-1)
a217793_tabf =
   map (\p -> [2*p*k + k^2 `mod` p | k <- [0..p-1]]) a065091_list

Formula

T(n,k) = 2*p*k + k^2 mod p with p = n-th odd prime and 0 <= k < p.