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Triangle read by rows where T(m,n)=2mn+m+n+4
9

%I #16 Aug 03 2014 14:26:17

%S 8,11,16,14,21,28,17,26,35,44,20,31,42,53,64,23,36,49,62,75,88,26,41,

%T 56,71,86,101,116,29,46,63,80,97,114,131,148,32,51,70,89,108,127,146,

%U 165,184,35,56,77,98,119,140,161,182,203,224

%N Triangle read by rows where T(m,n)=2mn+m+n+4

%C The terms form a subset of A153039 because 2*T(m,n)-7=(2n+1)(2m+1) are not prime.

%H Vincenzo Librandi, <a href="/A154685/b154685.txt">Rows n = 1..100, flattened</a>

%F T(m,n) = A155724 + 8. - _L. Edson Jeffery_, Oct 12 2012

%e Triangle begins:

%e 8;

%e 11, 16;

%e 14, 21, 28;

%e 17, 26, 35, 44;

%e 20, 31, 42, 53, 64;

%e 23, 36, 49, 62, 75, 88;

%e 26, 41, 56, 71, 86, 101, 116;

%e 29, 46, 63, 80, 97, 114, 131, 148;

%e 32, 51, 70, 89, 108, 127, 146, 165, 184;

%e 35, 56, 77, 98, 119, 140, 161, 182, 203, 224;

%t Flatten@Table[2*n*m+m+n+4,{n,20},{m,n}] (* _Vincenzo Librandi_, Jan 29 2012 *)

%o (PARI) for(m=1,9,for(n=1,m,print1(2*m*n+m+n+4", "))) \\ _Charles R Greathouse IV_, Dec 27 2011

%Y Cf. A153039, A089192, A155724.

%Y Row sums: A151675. - _N. J. A. Sloane_, May 31 2009

%K nonn,tabl,easy

%O 1,1

%A _Vincenzo Librandi_, Jan 18 2009

%E Clarified comment. - _R. J. Mathar_, Jan 24 2009