A123566 Table (read by antidiagonals) where t(1,n) = t(m,1) = 1 and where t(m,n) = lcm(Sum_{k=1..m-1} t(k,n), Sum_{j=1..n-1} t(m,j)).

1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 4, 3, 4, 1, 1, 8, 30, 30, 8, 1, 1, 16, 36, 35, 36, 16, 1, 1, 32, 1224, 630, 630, 1224, 32, 1, 1, 64, 14256, 868700, 675, 868700, 14256, 64, 1, 1, 128, 1010880, 4140952200, 1174420350, 1174420350, 4140952200, 1010880, 128, 1, 1

Offset

1,8

Links

Table of n, a(n) for n=1..56.

Example

t(5,3) = lcm(Sum_{k=1..4} t(k,3), Sum_{j=1..2} t(5,j)) = lcm(1+2+3+30, 1+8) = lcm(36,9) = 36.

Mathematica

t[m_, n_] := t[m, n] = If[m == 1 || n == 1, 1, LCM[Sum[t[k, n], {k, m - 1}], Sum[t[m, j], {j, n - 1}]]]; Flatten@Table[t[d + 1 - j, j], {d, 11}, {j, d}] (* Ray Chandler, Nov 19 2006 *)

Crossrefs

Sequence in context: A116595 A128315 A198329 * A279863 A201757 A053390

Adjacent sequences: A123563 A123564 A123565 * A123567 A123568 A123569

Keyword

nonn,tabl

Author

Leroy Quet, Nov 12 2006

Extensions

Extended by Ray Chandler, Nov 19 2006

Status

approved