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%I #14 Sep 08 2022 08:45:40
%S -5,-2,3,1,8,15,4,13,22,31,7,18,29,40,51,10,23,36,49,62,75,13,28,43,
%T 58,73,88,103,16,33,50,67,84,101,118,135,19,38,57,76,95,114,133,152,
%U 171,22,43,64,85,106,127,148,169,190,211,25,48,71,94,117,140,163,186,209
%N Triangle read by rows where T(m,n)=2*m*n + m + n - 9.
%C The numbers 2*T(m,n)+19 =(2*n+1)*(2*m+1) are not prime.
%C First column: A016777, second column: A016885, third column: A016993, fourth column: A017209. - _Vincenzo Librandi_, Nov 20 2012
%H Vincenzo Librandi, <a href="/A155551/b155551.txt">Rows n = 1..100, flattened</a>
%e Triangle begins:
%e -5;
%e -2, 3;
%e 1, 8, 15;
%e 4, 13, 22, 31;
%e 7, 18, 29, 40, 51;
%e 10, 23, 36, 49, 62, 75;
%e 13, 28, 43, 58, 73, 88, 103;
%e 16, 33, 50, 67, 84, 101, 118, 135;
%e 19, 38, 57, 76, 95, 114, 133, 152, 171;
%e 22, 43, 64, 85, 106, 127, 148, 169, 190, 211; etc.
%t t[n_,k_]:=2 n*k + n + k - 9; Table[t[n, k], {n, 15}, {k, n}]//Flatten (* _Vincenzo Librandi_, Nov 20 2012 *)
%o (Magma) [2*n*k + n + k - 9: k in [1..n], n in [1..11]]; // _Vincenzo Librandi_, Nov 20 2012
%Y Cf. A153143, A153144, A016777, A016885, A016993, A017209.
%K tabl,sign,easy
%O 1,1
%A _Vincenzo Librandi_, Jan 24 2009
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