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A163657
Triangle T(m,n) = 2*m*n + m + n + 8 read by rows.
6
12, 15, 20, 18, 25, 32, 21, 30, 39, 48, 24, 35, 46, 57, 68, 27, 40, 53, 66, 79, 92, 30, 45, 60, 75, 90, 105, 120, 33, 50, 67, 84, 101, 118, 135, 152, 36, 55, 74, 93, 112, 131, 150, 169, 188, 39, 60, 81, 102, 123, 144, 165, 186, 207, 228, 42, 65, 88, 111, 134, 157, 180
OFFSET
1,1
COMMENTS
If p=2*n+1 is a prime number, then T(n,n) = (p^2+15)/2.
First column: 3*A020705; second column: 5*A020705; third column: A017029. - Vincenzo Librandi, Nov 18 2012
LINKS
Vincenzo Librandi, Rows n = 1..100, flattened
FORMULA
T(n,m) = A163672(n,m)+1.
EXAMPLE
Triangle begins:
12;
15, 20;
18, 25, 32;
21, 30, 39, 48;
24, 35, 46, 57, 68;
27, 40, 53, 66, 79, 92;
30, 45, 60, 75, 90, 105, 120;
33, 50, 67, 84, 101, 118, 135, 152; etc.
MATHEMATICA
Flatten[Table[2nm + m + n + 8, {n, 10}, {m, n}]] (* Vincenzo Librandi, Nov 18 2012 *)
PROG
(Magma) [2*n*k+n+k+8: k in [1..n], n in [1..11]]; // Vincenzo Librandi, Nov 18 2012
CROSSREFS
KEYWORD
nonn,easy,tabl
AUTHOR
Vincenzo Librandi, Aug 02 2009
EXTENSIONS
Edited by R. J. Mathar, Oct 12 2009
STATUS
approved