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Triangle read by rows, A051731 * A158948
2

%I #3 Mar 03 2013 14:17:02

%S 1,2,1,3,0,1,4,2,0,1,4,0,1,0,1,7,2,1,1,0,1,5,0,1,0,1,0,1,8,3,0,2,0,1,

%T 0,18,0,2,0,1,0,1,0,1,10,2,1,1,1,1,0,1,0,1

%N Triangle read by rows, A051731 * A158948

%C Row sums = sigma(n), A000203. Left column = A079247

%F Triangle read by rows, A051731 * A158948

%e First few rows of the triangle =

%e 1;

%e 2, 1;

%e 3, 0, 1;

%e 4, 2, 0, 1;

%e 4, 0, 1, 0, 1;

%e 7, 2, 1, 1, 0, 1;

%e 5, 0, 1, 0, 1, 0, 1;

%e 8, 3, 0, 2, 0, 1, 0, 1;

%e 8, 0, 2, 0, 1, 0, 1, 0, 1;

%e 10, 2, 1, 1, 1, 1, 0, 1, 0, 1;

%e 7, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1;

%e 15, 4, 1, 3, 0, 2, 0, 10, 1, 0, 1;

%e 8, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1;

%e 13, 2, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1;

%e ...

%Y Cf. A158948, A000203, A051731

%K nonn,tabl

%O 1,2

%A _Gary W. Adamson_ & _Mats Granvik_, Mar 31 2009