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Euler-Seidel matrix T(k,n) with start sequence A001147, read by antidiagonals.
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%I #15 Jul 06 2023 07:04:41

%S 1,1,0,2,1,1,4,2,1,0,10,6,4,3,3,26,16,10,6,3,0,76,50,34,24,18,15,15,

%T 232,156,106,72,48,30,15,0,764,532,376,270,198,150,120,105,105,2620,

%U 1856,1324,948,678,480,330,210,105,0,9496,6876,5020,3696,2748,2070,1590,1260,1050,945,945

%N Euler-Seidel matrix T(k,n) with start sequence A001147, read by antidiagonals.

%C In an Euler-Seidel matrix, the rows are consecutive pairwise sums and the columns consecutive differences, with the first column the inverse binomial transform of the start sequence.

%H Alois P. Heinz, <a href="/A099020/b099020.txt">Rows n = 0..140, flattened</a>

%H D. Dumont, <a href="http://www.mat.univie.ac.at/~slc/opapers/s05dumont.html">Matrices d'Euler-Seidel</a>, Sem. Loth. Comb. B05c (1981) 59-78.

%F Recurrence: T(0, 2n) = (2n-1)!!, T(0, 2n+1) = 0, T(k, n) = T(k-1, n) + T(k-1, n+1).

%e 1, 0, 1, 0, 3, 0, 15, ...

%e 1, 1, 1, 3, 3, 15, 15, ...

%e 2, 2, 4, 6, 18, 30, 120, ...

%e 4, 6, 10, 24, 48, 150, 330, ...

%e 10, 16, 34, 72, 198, 480, 1590, ...

%p T:= proc(k, n) option remember; `if`(k=0, `if`(irem(n, 2)=0,

%p doublefactorial(n-1), 0), T(k-1, n) +T(k-1, n+1))

%p end:

%p seq(seq(T(d-n, n), n=0..d), d=0..14); # _Alois P. Heinz_, Oct 14 2012

%t t[0, n_?EvenQ] := (n-1)!!; t[0, n_?OddQ] := 0; t[k_, n_] := t[k, n] = t[k-1, n] + t[k-1, n+1]; Table[t[k-n, n], {k, 0, 10}, {n, 0, k}] // Flatten (* _Jean-François Alcover_, Dec 10 2012 *)

%Y First column is A000085, 2nd A013989, main diagonal is in A099021.

%K nonn,tabl

%O 0,4

%A _Ralf Stephan_, Sep 23 2004