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%I #16 Dec 28 2021 11:17:12
%S 1,1,1,1,1,1,1,2,1,1,1,2,1,1,1,1,3,1,2,1,1,1,3,1,2,1,1,1,1,4,1,3,1,2,
%T 1,1,1,4,1,3,1,2,1,1,1,1,5,1,4,1,3,1,2,1,1,1,5,1,4,1,3,1,2,1,1,1
%N Triangle read by rows, A070909 * A177990
%C Row sums = A117142: (1, 2, 3, 5, 6, 9,...)
%H Peter Bala, <a href="/A177994/a177994.pdf">Matrices with repeated columns - the generalised Appell groups</a>
%F As infinite lower triangular matrices, A070909 * A177990
%e First few rows of the triangle =
%e 1;
%e 1, 1;
%e 1, 1, 1;
%e 1, 2, 1, 1;
%e 1, 2, 1, 1, 1;
%e 1, 3, 1, 2, 1, 1;
%e 1, 3, 1, 2, 1, 1, 1;
%e 1, 4, 1, 3, 1, 2, 1, 1;
%e 1, 4, 1, 3, 1, 2, 1, 1, 1;
%e 1, 5, 1, 4, 1, 3, 1, 2, 1, 1;
%e 1, 5, 1, 4, 1, 3, 1, 2, 1, 1, 1;
%e 1, 6, 1, 5, 1, 4, 1, 3, 1, 2, 1, 1;
%e 1, 6, 1, 5, 1, 4, 1, 3, 1, 2, 1, 1, 1;
%e 1, 7, 1, 6, 1, 5, 1, 4, 1, 3, 1, 2, 1, 1;
%e 1, 7, 1, 6, 1, 5, 1, 4, 1, 3, 1, 2, 1, 1, 1;
%e ...
%Y A177994 = A177990 * A070909.
%Y Cf. A117142.
%K nonn,tabl
%O 0,8
%A _Gary W. Adamson_, May 16 2010
%E a(28)=1 inserted before the first "4" by _Georg Fischer_, Dec 28 2021