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%I #93 Apr 09 2023 02:32:03
%S 1,1,1,1,1,1,1,1,0,1,0,1,1,1,0,1,0,1,1,1,0,1,0,1,1,1,1,0,0,1,0,0,1,1,
%T 0,1,0,0,1,0,1,1,1,0,1,0,0,1,0,0,1,1,0,1,0,1,1,0,0,1,1,0,1,0,0,1,1,0,
%U 0,0,1,1,1,0,1,0,0,0,1,0,0,0,1,1,0,0,1,0,0,0,1,0,1,1,1,1,0,0,1,0,0,0,1,0,0,0
%N Irregular triangle read by rows: T(n,k) is the number of partitions of n into 2*k-1 consecutive parts, n >= 1, k >= 1. Column k lists 1's interleaved with 2*k-2 zeros, and the first element of column k is in row A000384(k).
%C Conjecture 1: T(n,k) is the number of subparts, in an octant of the symmetric representation of sigma(n), that arises from the (2*k-1)-th double-staircase of the double-staircases diagram of n described in A335616.
%C Conjecture 2: Indices of 1's coincide with indices of nonzero terms in A347263, A347529, A351819.
%C For the above conjectures see also the "ziggurat" diagram described in A347186.
%C This triangle is formed by the odd-indexed columns of the triangle A237048.
%C Terms can be 0 or 1.
%H Paolo Xausa, <a href="/A351824/b351824.txt">Table of n, a(n) for n = 1..10490</a> (rows 1..800 of triangle, flattened).
%F T(n,k) = A352499(n,k)/n. - _Omar E. Pol_, Mar 24 2022
%F T(n,k) = [(2*k-1)|n], where 1 <= k <= floor((sqrt(8*n+1)+1)/4) and [] is the Iverson bracket. - _Paolo Xausa_, Apr 01 2023
%e Triangle begins:
%e -----------------------
%e n / k 1 2 3 4
%e -----------------------
%e 1 | 1;
%e 2 | 1;
%e 3 | 1;
%e 4 | 1;
%e 5 | 1;
%e 6 | 1, 1;
%e 7 | 1, 0;
%e 8 | 1, 0;
%e 9 | 1, 1;
%e 10 | 1, 0;
%e 11 | 1, 0;
%e 12 | 1, 1;
%e 13 | 1, 0;
%e 14 | 1, 0;
%e 15 | 1, 1, 1;
%e 16 | 1, 0, 0;
%e 17 | 1, 0, 0;
%e 18 | 1, 1, 0;
%e 19 | 1, 0, 0;
%e 20 | 1, 0, 1;
%e 21 | 1, 1, 0;
%e 22 | 1, 0, 0;
%e 23 | 1, 0, 0;
%e 24 | 1, 1, 0;
%e 25 | 1, 0, 1;
%e 26 | 1, 0, 0;
%e 27 | 1, 1, 0;
%e 28 | 1, 0, 0, 1;
%e ...
%e For n = 15 the partitions of 15 into an odd number of consecutive parts are [15], [6, 5, 4] and [5, 4, 3, 2, 1]. There are a partition with only one part, a partition with three parts and a partition with five parts, so the 15th row of triangle is [1, 1, 1].
%t A351824[rowmax_]:=Table[Boole[Divisible[n,2k-1]],{n,rowmax},{k,Floor[(Sqrt[8n+1]+1)/4]}];A351824[50] (* _Paolo Xausa_, Apr 01 2023 *)
%Y Row sums give A082647.
%Y Row n has length A351846(n).
%Y Cf. A000384, A196020, A235791, A236104, A237048, A237270, A237271, A237591, A237593, A244250, A262619, A262626, A279387, A280850, A280851, A286000, A286001, A296508, A299765, A335616, A347186, A347263, A347529, A348854, A351819, A352257, A352499.
%K nonn,tabf,easy
%O 1
%A _Omar E. Pol_, Feb 20 2022