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A328027 Irregular triangle read by rows where row n lists, in weakly increasing order, the differences between consecutive divisors of n.

%I A328027 #4 Oct 03 2019 08:40:02
%S A328027 1,2,1,2,4,1,1,3,6,1,2,4,2,6,1,3,5,10,1,1,1,2,6,12,1,5,7,2,2,10,1,2,4,
%T A328027 8,16,1,1,3,3,9,18,1,1,2,5,10,2,4,14,1,9,11,22,1,1,1,2,2,4,12,4,20,1,
%U A328027 11,13,2,6,18,1,2,3,7,14,28,1,1,1,2,4,5,15
%N A328027 Irregular triangle read by rows where row n lists, in weakly increasing order, the differences between consecutive divisors of n.
%e A328027 Triangle begins:
%e A328027    {}
%e A328027    1
%e A328027    2
%e A328027    1  2
%e A328027    4
%e A328027    1  1  3
%e A328027    6
%e A328027    1  2  4
%e A328027    2  6
%e A328027    1  3  5
%e A328027   10
%e A328027    1  1  1  2  6
%e A328027   12
%e A328027    1  5  7
%e A328027    2  2 10
%e A328027    1  2  4  8
%e A328027   16
%e A328027    1  1  3  3  9
%e A328027   18
%e A328027    1  1  2  5 10
%e A328027    2  4 14
%e A328027    1  9 11
%e A328027   22
%e A328027    1  1  1  2  2  4 12
%e A328027 For example, the divisors of 18 are {1,2,3,6,9,18}, with differences {1,1,3,3,9}, which is row 18.
%t A328027 Table[Sort[Differences[Divisors[n]]],{n,30}]
%Y A328027 Same as A193829 with rows sorted in increasing order.
%Y A328027 Same as A328025 with rows reversed.
%Y A328027 Row sums are A001477.
%Y A328027 Row lengths are A000005.
%Y A328027 First column is A060680.
%Y A328027 Cf. A027750, A060681, A060682, A060683, A070211, A129308, A328024.
%K A328027 nonn,tabf
%O A328027 1,2
%A A328027 _Gus Wiseman_, Oct 02 2019