cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A327583 Number T(n,k) of colored compositions of n using all colors of a k-set such that all parts have different color patterns and the patterns for parts i have i distinct colors in increasing order; triangle T(n,k), n>=0, min(j:A001787(j)>=n)<=k<=n, read by rows.

This page as a plain text file.
%I A327583 #29 Feb 22 2021 09:22:07
%S A327583 1,1,3,4,13,6,48,75,150,536,541,300,2820,6320,4683,666,11144,50150,
%T A327583 81012,47293,936,41346,308080,903210,1134952,545835,1824,131304,
%U A327583 1689040,7805080,16914786,17346352,7087261,2520,420084,8279640,58728660,194051060,333027016
%N A327583 Number T(n,k) of colored compositions of n using all colors of a k-set such that all parts have different color patterns and the patterns for parts i have i distinct colors in increasing order; triangle T(n,k), n>=0, min(j:A001787(j)>=n)<=k<=n, read by rows.
%C A327583 T(n,k) is defined for all n>=0 and k>=0.  The triangle displays only positive terms.  All other terms are zero.
%H A327583 Alois P. Heinz, <a href="/A327583/b327583.txt">Rows n = 0..150, flattened</a>
%e A327583 T(3,2) = 4: 2ab1a, 2ab1b, 1a2ab, 1b2ab.
%e A327583 T(3,3) = 13: 3abc, 2ab1c, 2ac1b, 2bc1a, 1a2bc, 1b2ac, 1c2ab, 1a1b1c, 1a1c1b, 1b1a1c, 1b1c1a, 1c1a1b, 1c1b1a.
%e A327583 T(4,2) = 6: 2ab1a1b, 1a2ab1b, 1a1b2ab, 2ab1b1a, 1b2ab1a, 1b1a2ab.
%e A327583 Triangle T(n,k) begins:
%e A327583   1;
%e A327583      1;
%e A327583         3;
%e A327583         4,  13;
%e A327583         6,  48,    75;
%e A327583            150,   536,    541;
%e A327583            300,  2820,   6320,   4683;
%e A327583            666, 11144,  50150,  81012,   47293;
%e A327583            936, 41346, 308080, 903210, 1134952, 545835;
%e A327583            ...
%p A327583 C:= binomial:
%p A327583 g:= proc(n) option remember; n*2^(n-1) end:
%p A327583 h:= proc(n) option remember; local k; for k from
%p A327583       `if`(n=0, 0, h(n-1)) do if g(k)>=n then return k fi od
%p A327583     end:
%p A327583 b:= proc(n, i, k, p) option remember; `if`(n=0, p!,
%p A327583       `if`(i<1 or k<h(n), 0, add(b(n-i*j, min(n-i*j, i-1),
%p A327583         k, p+j)*C(C(k, i), j), j=0..n/i)))
%p A327583     end:
%p A327583 T:= (n, k)-> add(b(n$2, i, 0)*(-1)^(k-i)*C(k, i), i=0..k):
%p A327583 seq(seq(T(n, k), k=h(n)..n), n=0..12);
%t A327583 c = Binomial;
%t A327583 g[n_] := g[n] = n*2^(n - 1);
%t A327583 h[n_] := h[n] = Module[{k}, For[k = If[n == 0, 0,
%t A327583      h[n - 1]], True, k++, If[g[k] >= n, Return[k]]]];
%t A327583 b[n_, i_, k_, p_] := b[n, i, k, p] = If[n == 0, p!,
%t A327583      If[i < 1 || k < h[n], 0, Sum[b[n - i*j, Min[n - i*j, i - 1],
%t A327583      k, p + j]*c[c[k, i], j], {j, 0, n/i}]]];
%t A327583 T[n_, k_] := Sum[b[n, n, i, 0]*(-1)^(k - i)*c[k, i], {i, 0, k}];
%t A327583 Table[Table[T[n, k], {k, h[n], n}], {n, 0, 12}] // Flatten (* _Jean-François Alcover_, Feb 22 2021, after _Alois P. Heinz_ *)
%Y A327583 Main diagonal gives A000670.
%Y A327583 Row sums give A321587.
%Y A327583 Column sums give A327585.
%Y A327583 Cf. A001787, A326914, A327584 (this triangle read by columns).
%K A327583 nonn,tabf
%O A327583 0,3
%A A327583 _Alois P. Heinz_, Sep 17 2019