A176798 - OEIS

%I #9 Sep 01 2016 06:56:41

%S 1,2,3,4,6,8,7,10,13,16,11,15,19,23,27,16,21,26,31,36,41,22,28,34,40,

%T 46,52,58,29,36,43,50,57,64,71,78,37,45,53,61,69,77,85,93,101,46,55,

%U 64,73,82,91,100,109,118,127,56,66,76,86,96,106,116,126,136,146,156

%N Triangle read by rows: T(n,m)=1 + n*(2*m + 1 + n)/2, 0<=m<=n.

%H Ivan Neretin, <a href="/A176798/b176798.txt">Table of n, a(n) for n = 0..5150</a>

%e 1;

%e 2, 3;

%e 4, 6, 8;

%e 7, 10, 13, 16;

%e 11, 15, 19, 23, 27;

%e 16, 21, 26, 31, 36, 41;

%e 22, 28, 34, 40, 46, 52, 58;

%e 29, 36, 43, 50, 57, 64, 71, 78;

%e 37, 45, 53, 61, 69, 77, 85, 93, 101;

%e 46, 55, 64, 73, 82, 91, 100, 109, 118, 127;

%e 56, 66, 76, 86, 96, 106, 116, 126, 136, 146, 156;

%p A176798 := proc(n,m)

%p     1+n*(2*m+1+n)/2 ;

%p end proc: # _R. J. Mathar_, Feb 18 2016

%t t[n_, m_] = 1 + n*(2*m + 1 + n)/2;

%t Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}];

%t Flatten[%]

%Y Cf. A081435 (row sums), A104249 (diagonal).

%K nonn,tabl,easy

%O 0,2

%A _Roger L. Bagula_, Apr 26 2010