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A155550 Triangle read by rows where T(m,n)=2*m*n + m + n - 6.

%I A155550 #10 Sep 08 2022 08:45:40
%S A155550 -2,1,6,4,11,18,7,16,25,34,10,21,32,43,54,13,26,39,52,65,78,16,31,46,
%T A155550 61,76,91,106,19,36,53,70,87,104,121,138,22,41,60,79,98,117,136,155,
%U A155550 174,25,46,67,88,109,130,151,172,193,214,28,51,74,97,120,143,166,189,212
%N A155550 Triangle read by rows where T(m,n)=2*m*n + m + n - 6.
%C A155550 Numbers n such that 2n+13 is not prime.
%C A155550 First column: A016777, second column: A016861, third column: A017029, fourth column: A017245. - _Vincenzo Librandi_, Nov 21 2012
%H A155550 Vincenzo Librandi, <a href="/A155550/b155550.txt">Rows n = 1..100, flattened</a>
%e A155550 Triangle begins:
%e A155550 -2;
%e A155550 1,  6;
%e A155550 4,  11, 18;
%e A155550 7,  16, 25, 34;
%e A155550 10, 21, 32, 43, 54;
%e A155550 13, 26, 39, 52, 65,  78;
%e A155550 16, 31, 46, 61, 76,  91,  106;
%e A155550 19, 36, 53, 70, 87,  104, 121, 138;
%e A155550 22, 41, 60, 79, 98,  117, 136, 155, 174;
%e A155550 25, 46, 67, 88, 109, 130, 151, 172, 193, 214; etc.
%t A155550 t[n_,k_]:= 2 n*k + n + k - 6; Table[t[n, k], {n, 15}, {k, n}]//Flatten (* _Vincenzo Librandi_, Nov 21 2012 *)
%o A155550 (Magma) [2*n*k + n + k - 6: k in [1..n], n in [1..11]]; // _Vincenzo Librandi_, Nov 21 2012
%Y A155550 Cf. A153082, A016777, A016861, A017029, A017245.
%K A155550 tabl,sign
%O A155550 1,1
%A A155550 _Vincenzo Librandi_, Jan 24 2009