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Triangle T(n,k) = k if k<n and k|n, = 0 otherwise, 1 <= k <= n; read by rows.
3

%I #7 Aug 08 2016 19:49:33

%S 1,1,0,1,0,0,1,2,0,0,1,0,0,0,0,1,2,3,0,0,0,1,0,0,0,0,0,0,1,2,0,4,0,0,

%T 0,0,1,0,3,0,0,0,0,0,0,1,2,0,0,5,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1,2,

%U 3,4,0,6,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,1,2,0,0,0,0,7,0,0,0,0,0,0,0

%N Triangle T(n,k) = k if k<n and k|n, = 0 otherwise, 1 <= k <= n; read by rows.

%C A variant of A127093, which has T(n,n) = n. [The original definition said "Subsequence of A127093". Since all nonnegative integers are repeated infinitely often in both sequences, each one is a subsequence of the other, but there is no such relation on a row-by-row basis. - _M. F. Hasler_, Aug 08 2016]

%C Let A=A176891*A176891, B=A*A, C=B*B, D=C*C and so on, then the leftmost column in the last matrix (D) converges to A165552.

%F T(n,k) = if n=1 and k=1 then 1 elseif n=k then 0 elseif k divides n then k else 0.

%e Triangle begins:

%e 1,

%e 1,0,

%e 1,0,0,

%e 1,2,0,0,

%e 1,0,0,0,0,

%e 1,2,3,0,0,0,

%e 1,0,0,0,0,0,0,

%e 1,2,0,4,0,0,0,0,

%Y Cf. A127093, A165552.

%K nonn,tabl

%O 1,8

%A _Gary W. Adamson_ and _Mats Granvik_, Apr 28 2010

%E Definition corrected by _M. F. Hasler_, Aug 08 2016