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A155705 Triangle read by rows where T(m,n) = 2*m*n + m + n + 2.

%I A155705 #23 Sep 08 2022 08:45:41
%S A155705 6,9,14,12,19,26,15,24,33,42,18,29,40,51,62,21,34,47,60,73,86,24,39,
%T A155705 54,69,84,99,114,27,44,61,78,95,112,129,146,30,49,68,87,106,125,144,
%U A155705 163,182,33,54,75,96,117,138,159,180,201,222,36,59,82,105,128,151
%N A155705 Triangle read by rows where T(m,n) = 2*m*n + m + n + 2.
%C A155705 2*T(m,n)-3 = (2*m+1)*(2*n+1) is not prime, obviously. Also: first column: 3*A020725; second column: A016897; third column: A017041; fourth column: 3*A016789. - _Vincenzo Librandi_, Nov 20 2012
%H A155705 Vincenzo Librandi, <a href="/A155705/b155705.txt">Rows n = 1..100, flattened</a>
%e A155705 Triangle begins:
%e A155705 6;
%e A155705 9,  14;
%e A155705 12, 19, 26;
%e A155705 15, 24, 33, 42;
%e A155705 18, 29, 40, 51, 62;
%e A155705 21, 34, 47, 60, 73,  86;
%e A155705 24, 39, 54, 69, 84,  99,  114;
%e A155705 27, 44, 61, 78, 95,  112, 129, 146;
%e A155705 30, 49, 68, 87, 106, 125, 144, 163, 182;
%e A155705 33, 54, 75, 96, 117, 138, 159, 180, 201, 222; etc.
%t A155705 t[n_,k_]:=2 n*k + n + k + 2; Table[t[n, k], {n, 11}, {k, n}]//Flatten (* _Vincenzo Librandi_, Nov 20 2012 *)
%o A155705 (Magma) [2*n*k + n + k + 2: k in [1..n],  n in [1..11]]; // _Vincenzo Librandi_, Nov 20 2012
%Y A155705 Cf. A153043, A020725, A016897, A017041.
%K A155705 nonn,tabl,easy
%O A155705 1,1
%A A155705 _Vincenzo Librandi_, Jan 25 2009