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%I #20 Apr 15 2024 13:13:06
%S 1,1,0,1,1,1,1,2,2,2,1,3,3,5,6,1,4,4,8,15,21,1,5,5,11,24,52,82,1,6,6,
%T 14,33,83,203,354,1,7,7,17,42,114,324,877,1671,1,8,8,20,51,145,445,
%U 1400,4140,8536,1,9,9,23,60,176,566,1923,6609,21147,46814
%N Array read by ascending antidiagonals. A(n, k) = (n-1)*Gould(k-1) + Bell(k) for n >= 0 and k >= 1, A(n, 0) = 1.
%C The array defines a family of Bell-like sequences. The case n = 1 are the Bell numbers A000110, case n = 0 is A032347 and case n = 2 is A038561. The n-th sequence r(k) = T(n, k) is defined for k >= 0 by the recurrence r(k) = Sum_{j=0..k-1} binomial(k-1, j)*r(j) with r(0) = 1 and r(1) = n.
%F Given a list T let PS(T) denote the list of partial sums of T. Given two list S and T let [S, T] denote the concatenation of the lists. Further let P[end] denote the last element of the list P. Row n of the array with length k can be computed by the following procedure:
%F A = [n], P = [1], R = [1];
%F Repeat k-1 times: R = [R, A], P = PS([A, P]), A = [P[end]];
%F Return R.
%e Array starts:
%e n\k 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, ...
%e ---------------------------------------------------------
%e [0] 1, 0, 1, 2, 6, 21, 82, 354, 1671, 8536, ... A032347
%e [1] 1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147, ... A000110
%e [2] 1, 2, 3, 8, 24, 83, 324, 1400, 6609, 33758, ... A038561
%e [3] 1, 3, 4, 11, 33, 114, 445, 1923, 9078, 46369, ... A038559
%e [4] 1, 4, 5, 14, 42, 145, 566, 2446, 11547, 58980, ... A352683
%e [5] 1, 5, 6, 17, 51, 176, 687, 2969, 14016, 71591, ...
%e [6] 1, 6, 7, 20, 60, 207, 808, 3492, 16485, 84202, ...
%e [7] 1, 7, 8, 23, 69, 238, 929, 4015, 18954, 96813, ...
%e [8] 1, 8, 9, 26, 78, 269, 1050, 4538, 21423, 109424, ...
%e [9] 1, 9, 10, 29, 87, 300, 1171, 5061, 23892, 122035, ...
%p alias(PS = ListTools:-PartialSums):
%p BellRow := proc(n, len) local a, k, P, T;
%p a := n; P := [1]; T := [1];
%p for k from 1 to len-1 do
%p T := [op(T), a]; P := PS([a, op(P)]); a := P[-1] od;
%p T end: seq(lprint(BellRow(n, 10)), n = 0..9);
%t nmax = 10;
%t BellRow[n_, len_] := Module[{a, k, P, T}, a = n; P = {1}; T = {1};
%t For[k = 1, k <= len - 1, k++,
%t T = Append[T, a]; P = Accumulate[Join[{a}, P]]; a = P[[-1]]];
%t T];
%t rows = Table[BellRow[n, nmax + 1], {n, 0, nmax}];
%t A[n_, k_] := rows[[n + 1, k + 1]];
%t Table[A[n - k, k], {n, 0, nmax}, {k, 0, n}] // Flatten (* _Jean-François Alcover_, Apr 15 2024, after _Peter Luschny_ *)
%o (Julia)
%o function BellRow(m, len)
%o a = m; P = BigInt[1]; T = BigInt[1]
%o for n in 1:len
%o T = vcat(T, a)
%o P = cumsum(vcat(a, P))
%o a = P[end]
%o end
%o T end
%o for n in 0:9 BellRow(n, 9) |> println end
%Y Rows: A032347, A000110 (Bell), A038561, A038559, A352683.
%Y Diagonals: A352684 (main).
%Y Cf. A040027 (Gould), A352686 (subtriangle).
%Y Compare A352680 for a similar array based on the Catalan numbers.
%K nonn,tabl
%O 0,8
%A _Peter Luschny_, Mar 28 2022
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