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A328025 Irregular triangle read by rows where row n gives the differences between consecutive divisors of n in weakly decreasing order.

%I A328025 #6 Oct 03 2019 08:39:53
%S A328025 1,2,2,1,4,3,1,1,6,4,2,1,6,2,5,3,1,10,6,2,1,1,1,12,7,5,1,10,2,2,8,4,2,
%T A328025 1,16,9,3,3,1,1,18,10,5,2,1,1,14,4,2,11,9,1,22,12,4,2,2,1,1,1,20,4,13,
%U A328025 11,1,18,6,2,14,7,3,2,1,28,15,5,4,2,1,1,1
%N A328025 Irregular triangle read by rows where row n gives the differences between consecutive divisors of n in weakly decreasing order.
%e A328025 Triangle begins:
%e A328025    {}
%e A328025    1
%e A328025    2
%e A328025    2  1
%e A328025    4
%e A328025    3  1  1
%e A328025    6
%e A328025    4  2  1
%e A328025    6  2
%e A328025    5  3  1
%e A328025   10
%e A328025    6  2  1  1  1
%e A328025   12
%e A328025    7  5  1
%e A328025   10  2  2
%e A328025    8  4  2  1
%e A328025   16
%e A328025    9  3  3  1  1
%e A328025   18
%e A328025   10  5  2  1  1
%e A328025 For example, the divisors of 18 are {1,2,3,6,9,18}, with differences {1,1,3,3,9}, so row 18 is {9,3,3,1,1}.
%t A328025 Table[Sort[Differences[Divisors[n]],Greater],{n,30}]
%Y A328025 Same as A193829 with rows sorted in weakly decreasing order.
%Y A328025 Same as A328027 with rows reversed.
%Y A328025 Row sums are A001477.
%Y A328025 Row lengths are A000005.
%Y A328025 First column is A060681.
%Y A328025 Heinz numbers of rows are A328023.
%Y A328025 Cf. A027750, A060680, A060682, A060683, A070211, A129308, A328024.
%K A328025 nonn,tabf
%O A328025 1,2
%A A328025 _Gus Wiseman_, Oct 02 2019