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A182720 Triangle read by rows: T(n,k) = A000041(k) if k divides n, T(n,k)=0 otherwise.

%I A182720 #6 Mar 30 2012 17:34:04
%S A182720 1,1,2,1,0,3,1,2,0,5,1,0,0,0,7,1,2,3,0,0,11,1,0,0,0,0,0,15,1,2,0,5,0,
%T A182720 0,0,22,1,0,3,0,0,0,0,0,30,1,2,0,0,7,0,0,0,0,42,1,0,0,0,0,0,0,0,0,0,
%U A182720 56,1,2,3,5,0,11,0,0,0,0,0,77,1,0,0,0,0,0,0,0,0,0,0,0,101,1,2,0,0,0,0,15,0,0,0,0,0,0,135,1,0,3,0,7,0,0,0,0,0,0,0,0,0,176
%N A182720 Triangle read by rows: T(n,k) = A000041(k) if k divides n, T(n,k)=0 otherwise.
%F A182720 T(n,k) = A051731(n,k)*A000041(k).
%e A182720 1,
%e A182720 1, 2,
%e A182720 1, 0, 3,
%e A182720 1, 2, 0, 5,
%e A182720 1, 0, 0, 0, 7,
%e A182720 1, 2, 3, 0, 0, 11,
%e A182720 1, 0, 0, 0, 0, 0, 15,
%e A182720 1, 2, 0, 5, 0, 0, 0, 22,
%e A182720 1, 0, 3, 0, 0, 0, 0, 0, 30,
%e A182720 1, 2, 0, 0, 7, 0, 0, 0, 0, 42
%p A182720 A182720 := proc(n,k) if n mod k = 0 then combinat[numbpart](k); else 0; end if ; end proc:
%p A182720 seq(seq(A182720(n,k),k=1..n),n=1..15) ;
%Y A182720 Cf. A000005, A000041, A051731, A168016, A168017, A168018, A168021. Positive integers of row n give A168017.
%Y A182720 Row sums give A047968.
%K A182720 nonn,easy,tabl
%O A182720 1,3
%A A182720 _Omar E. Pol_, Nov 28 2010