A246690 Number A(n,k) of compositions of n into parts of the k-th list of distinct parts in the order given by A246688; square array A(n,k), n>=0, k>=0, read by antidiagonals.
1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 2, 0, 1, 0, 1, 1, 0, 3, 1, 1, 0, 1, 0, 1, 1, 5, 0, 1, 0, 1, 1, 0, 2, 0, 8, 1, 1, 0, 1, 0, 1, 0, 3, 0, 13, 0, 1, 0, 1, 0, 1, 1, 1, 4, 1, 21, 1, 1, 0, 1, 1, 0, 1, 2, 0, 6, 0, 34, 0, 1, 0, 1, 1, 2, 0, 1, 3, 0, 9, 0, 55, 1, 1, 0
Offset: 0
Examples
Square array A(n,k) begins: 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ... 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, ... 0, 1, 1, 2, 0, 1, 0, 1, 1, 0, 2, 1, 1, 0, 2, ... 0, 1, 0, 3, 1, 2, 0, 1, 1, 0, 4, 1, 0, 0, 3, ... 0, 1, 1, 5, 0, 3, 1, 2, 1, 0, 7, 1, 2, 0, 6, ... 0, 1, 0, 8, 0, 4, 0, 3, 2, 1, 13, 2, 0, 0, 10, ... 0, 1, 1, 13, 1, 6, 0, 4, 2, 0, 24, 3, 3, 1, 18, ... 0, 1, 0, 21, 0, 9, 0, 5, 3, 0, 44, 4, 0, 0, 31, ... 0, 1, 1, 34, 0, 13, 1, 7, 4, 0, 81, 5, 5, 0, 55, ... 0, 1, 0, 55, 1, 19, 0, 10, 5, 0, 149, 6, 0, 0, 96, ... 0, 1, 1, 89, 0, 28, 0, 14, 7, 1, 274, 8, 8, 0, 169, ...
Links
- Alois P. Heinz, Antidiagonals n = 0..140
Crossrefs
Columns k=0-21, 23, 25-28 give: A000007, A000012, A059841, A000045(n+1), A079978, A000930, A121262, A003269(n+1), A182097, A079998, A000073(n+2), A003520, A079977, A079979, A060945, A005708, A001687(n+1), A017817, A082784, A079971, A006498, A005709, A052920, A120400, A060961, A005710, A013979.
Main diagonal gives A246691.
Programs
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Maple
b:= proc(n, i) b(n, i):= `if`(n=0, [[]], `if`(i>n, [], [map(x->[i, x[]], b(n-i, i+1))[], b(n, i+1)[]])) end: f:= proc() local i, l; i, l:=0, []; proc(n) while n>=nops(l) do l:=[l[], b(i, 1)[]]; i:=i+1 od; l[n+1] end end(): g:= proc(n, l) option remember; `if`(n=0, 1, add(`if`(i>n, 0, g(n-i, l)), i=l)) end: A:= (n, k)-> g(n, f(k)): seq(seq(A(n, d-n), n=0..d), d=0..14);
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Mathematica
b[n_, i_] := b[n, i] = If[n == 0, {{}}, If[i>n, {}, Join[Prepend[#, i]& /@ b[n - i, i + 1], b[n, i + 1]]]]; f = Module[{i = 0, l = {}}, Function[n, While[n >= Length[l], l = Join[l, b[i, 1]]; i++]; l[[n + 1]]]]; g[n_, l_] := g[n, l] = If[n==0, 1, Sum[If[i>n, 0, g[n - i, l]], {i, l}]]; A[n_, k_] := g[n, f[k]]; Table[Table[A[n, d - n], {n, 0, d}], {d, 0, 14}] // Flatten (* Jean-François Alcover, Dec 07 2020, after Alois P. Heinz *)
Comments