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A154681
Triangle read by rows where T(m,n) = 2*m*n + m + n +3.
2
7, 10, 15, 13, 20, 27, 16, 25, 34, 43, 19, 30, 41, 52, 63, 22, 35, 48, 61, 74, 87, 25, 40, 55, 70, 85, 100, 115, 28, 45, 62, 79, 96, 113, 130, 147, 31, 50, 69, 88, 107, 126, 145, 164, 183, 34, 55, 76, 97, 118, 139, 160, 181, 202, 223, 37, 60, 83, 106, 129, 152
OFFSET
1,1
COMMENTS
2*T(m,n) - 5 = (2*n+1)*(2*m+1) is not prime.
First column: A112414; second column: A008587.
LINKS
Vincenzo Librandi, Rows n = 1..100, flattened
EXAMPLE
Triangle begins:
7;
10, 15;
13, 20, 27;
16, 25, 34, 43;
19, 30, 41, 52, 63;
22, 35, 48, 61, 74, 87;
25, 40, 55, 70, 85, 100, 115;
28, 45, 62, 79, 96, 113, 130, 147;
31, 50, 69, 88, 107, 126, 145, 164, 183;
34, 55, 76, 97, 118, 139, 160, 181, 202, 223; etc.
MATHEMATICA
t[n_, k_]:=2 n*k + n + k + 3; Table[t[n, k], {n, 10}, {k, n}]//Flatten (* _vincenzo Librandi_, Nov 17 2012 *)
PROG
(Magma) [(2*n*k + n + k + 3): k in [1..n], n in [1..11]]; // Vincenzo Librandi, Nov 17 2012
CROSSREFS
KEYWORD
nonn,tabl,easy
AUTHOR
Vincenzo Librandi, Jan 18 2009
STATUS
approved